Ed Dunham
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| (Former Meteorologist & CFHC Forum Moderator (Ed Passed Away on May 14, 2017)) |
| Mon Jul 02 2007 11:59 PM |
Waiting...But Not Quite There Yet
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Sunday 07/08 11AM (EDST) Update
All quiet on the eastern front. Looking at SST anomalies, the MJO (active Pacific - quiet Atlantic & Indian Oceans), and pressure patterns (surface and aloft), the Atlantic basin seems likely to stay quiet for awhile.
ED
Wednesday 07/04 Noon (EDST) Update
Invest 96L LLCC located near 10.8N 43.7W at 04/15Z continues to move just north of due west at about 15 knots. Minimal convection remains displaced to the south of the circulation center - perhaps under the influence of modest upper level northerly wind shear. Airmass is quite dry immediately north of the system with little change expected over the next few days as the system continues on a west to west northwest track. Overall wind shear is still expected to remain light for the next couple of days, however, an upper level low currently near 14N 60W is forecast to move slowly northward to near 20N 60W by Saturday morning - thus the system will be moving into an increasingly hostile upper air environment by the end of the week.
Still a couple of days for some additional minimal development to occur if the northerly shear relaxes and allows convection to wrap around the north side of the LLCC. But no TD likely unless this happens - with this system you definately need the convection to wrap to the north side and serve as a catalyst for a little intensification before the system encounters the wind shear associated with the upper level low and begins to weaken.
The dry air to the north has kept any deep convection from developing to the north of the circulation thus far, so 96L has not yet met the qualifications for TD status.
ED
Original Post
Since the previous thread is now quite outdated, and since there is some modest interest in a tropical wave located in the mid tropical Atlantic - a new thread seems to be in order.
The weak low along the tropical wave was located near 10N 39W at 03/00Z with movement toward the west at about 15 knots. The system has fair organization and has managed to maintain some convection today in spite of some rather dry air to its north. Wind shear is low and expected to remain low for a few more days as the system continues on its westward journey. SST's are certainly warm enough in the mid Atlantic so there is a small chance that this feature might do something - eventually - but probably not much. The season is still early.
From HanKFranK:
"Yesterday i saw the ITCZ blip at low latitude out near 35w and said 'nah.' today the thing has gained a tad of latitude and has a slightly better signature (if a tad less convection). I'm still saying 'nah' to myself, but maybe tilting my head at it a bit more. it looks like a reasonably favorable upper pattern will accompany it westward, though the environment is quite dry and its amplitude isn't anything to write home about. just the same, might bear a bit of watching. things rarely happen out there this early, but there is some precedent.
Mess near the north American continent is of the less interesting variety. the weak low near Florida is reduced to a frontal trough closer to Bermuda than anywhere.. still some weak shortwave energy along the sagging frontal boundary that is trying to wash out in the southeast. not much doing just yet."
HF 2249z02july
From Storm Hunter:
"Agree with hank... out near 40w. Some of the Globals take this into the Caribbean in a few days. Its pretty dry out there, and there is some Dust around. Based on the pattern, this wave should keeping moving wnw. I also see that the CMC wants to throw up something of Florida east cost in a few days. VERY WEAK... I would keep my eye on the wave in the Atlantic... if it holds, i would expect an invest from navy on it tomorrow."
Otherwise, nothing else of even minor significance is evident in the basin - but we'll all keep a casual lookout just in case a mid July surprise pops up. Since nothing much is really going on - at least not yet - feel free to comment on the above mentioned wave or any others that might generate a spark of interest in the basin over the next couple of weeks.
ED
| Clark |
| (Meteorologist) |
| Tue Jul 03 2007 01:19 AM |
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Re: Waiting...But Not Quite There Yet
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I'll chime in with some thoughts on that thing in the central Atlantic as well.
I am *kinda* intrigued by the low in the central Atlantic. It's the most interesting thing out there since Barry, to me at least, but I still don't give it much of a shot in the short-term. It's one of those things where if you saw it come August, the alarms would be going off and everyone everywhere would be talking about it, but being the start of July it only merits a passing mention. The environment is just too stable out there right now, largely driven by fairly cool SSTs and ENEly wind surges around the subtropical ridge near the Azores. (This plot shows the end result fairly well.)
However, things improve as it nears the Lesser Antilles -- waters get warmer, the atmosphere becomes more unstable, and there's not a whole lot of shear to speak of right now. If it can hold together another 4-5 days or so, it could get interesting. We are slowly transitioning into that time of year where when things look interesting in the central Atlantic, they can pose problems (re: potential development) further west several days later.
Not really intrigued by the stuff hanging around the southeast coast. If it sat for 5 days and had something to organize around, like a mid-level vortex from some daytime convection dropping into the open waters, it might get intriguing...but if the central Atlantic feature is a 2 out of 10 on the development scale for the next three days, this is a 0.5.
If neither get going -- we could be waiting a couple of weeks into July. Others who know a lot more about intraseasonal and long-range tropical forecasting than I do suggest that things should start to get somewhat favorable basin-wide in about three weeks -- moreso than climatology alone would suggest, at least -- so if nothing develops in the short-term, I say enjoy the respite as things could ramp up fairly quickly on down the line.
| Storm Hunter |
| (Veteran Storm Chaser) |
| Tue Jul 03 2007 04:11 AM |
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Re: Waiting...But Not Quite There Yet
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hmm... Ramsdis Floater Moved... and looks like there is a nice set of storms tonight!
Much better than last night.... Little thing is trying to flare up. I don't see that much shear, like clark noted above, maybe some from the NE, but not that strong. Dry air to the north of the system and some to the west. If the current trend holds... i would expect an invest in morning. Floater
| Storm Hunter |
| (Veteran Storm Chaser) |
| Tue Jul 03 2007 04:26 AM |
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Re: Waiting...But Not Quite There Yet
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Something of interest i spotted tonight... on the NHC sat page
http://www.nhc.noaa.gov/satellite.shtml
under Atlantic Floater 1 it has:
INVEST
Not sure if it means anything, it may just be something new this year? (Others have Not active and Test Float)
It points to this feature:
http://www.ssd.noaa.gov/goes/flt/t1/loop-vis.html
*** this could be a graphical error, or a human error typo, or that this is just an investigated area? I haven't seen any msgs from the Navy, yet!
| Lamar-Plant City |
| (Storm Tracker) |
| Tue Jul 03 2007 04:43 AM |
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Re: Waiting...But Not Quite There Yet
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I just noticed that about 10 minutes ago too. That's our little darling out in the mid-Atlantic showing up under INVEST on NHC. Maybe they are anticipating the Navy a bit, although I am not exactly clear how that designation stuff works. It certainly has a nice little flare-up of convection on the northeast side tonight, but will need a lot more getting together before it gets really interesting. I always have trouble with scale when they are that far away since there is no land near and few of the satellites give a good view if they HAVE land in them. At least it is something to look at this early in the season. Keep us posted.
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danielw
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| (Moderator) |
| Tue Jul 03 2007 04:49 AM |
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Wave nearing 40W Longitude
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EUMETSAT IR Satellite imagery.
Sector 4 EUMETSAT-copyright 2007 EUMETSAT
RAMSDIS shortwave imagery from 0015Z to 0345Z.
SSD "Investigation" Floater 1 from 2345Z to 0315Z.
INVEST
At 0315Z center of convection is located near 9.5N / 37.5W. Lightning has increased quite a bit over the last 3 hours. Diurnal convection-probably.
Strange formation to the main cloud area. While the lower level clouds would suggest the larger 'main' cloud is over the center of circulation. A semicircular notch exists to the NW side of the 'main' cloud. Resembling a 3/4 "Eye". No rotation about this notch is visible.
(Thanks to SSD for the Lat/ Long Grid overlay for this area of the Atlantic)
Current Dvorak cloud temperatures are in the -64 to -69C range. (colored as black). A short period of higher cloud tops existed around 0215Z. With the Dvorak indicating cloud tops in the -70 to -75C temperature range. (colored as white).
Current motion appears to be WNW near 15 knots.
| Storm Hunter |
| (Veteran Storm Chaser) |
| Tue Jul 03 2007 04:50 AM |
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Re: Wave nearing 40W Longitude
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Somebody's working late tonight
96L.INVEST
| dem05 |
| (User) |
| Tue Jul 03 2007 05:04 AM |
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Re: Waiting...But Not Quite There Yet
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Edit to first paragraph: Hi Hunter...Saw you posted while I was typing. We have 96L now, my first paragraph is somewhat "moot" now. Good catch!
FYI...the invest has been up for quite some time now on the mid-Atlantic feature. From best I can tell you, since about 8 pm "ish". I had dinner with the family, so it may have been up longer than that. Since a TWO has come out since the posting of the feature as an invest on the satellite page, I do not expect significant changes in in the invest catgorization (number assignment) and/or 5:30AM TWO unless there is continued progress in organization and/or a status quo in organization. Like other Invests we have seen this year, it apparently has peaked some interests inthe Meteorology community, but it is not enough yet to merit an invest number (i.e. 96L).
The area has undoubtably been battling the stability situation with a level of tennacity and my belief is that it has continued to organize further somewhat. The formation of a Tropical Depression from this while it is out there is not impossible. However, I highly agree with Clark's synopsis also and a system this far out is also a little beyond climo expectations for development. It gets a better shot closer to the leewards in 5 days if it sustains itself, but 5 days is a very long time and a lot can happen (including the idea that this wave could go POOF!). So I'd keep an eye on something possibly happenning with it days +3-+5 (with no guarantees of development). If it does manage to develop before then...track it, but keep in mind that development out there is some what of an anomoly. From a scientific view of anomolies, such events may not be reflective of the rest of the season's activity. Mean time, have fun watching the satellite loops!
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danielw
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| (Moderator) |
| Tue Jul 03 2007 05:05 AM |
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Re: Wave nearing 40W Longitude
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Update.
Preliminary model run indicates the system could be in an area between 12.3N/ 56.0W and 17.3N/ 61.0W at 120 hours, or July 7 0000Z (8pmEDT on July 6th).
That area would still be East of the Lesser Antilles.
And at 30 knots maximum wind speed. Less than Tropical Storm status
| Storm Hunter |
| (Veteran Storm Chaser) |
| Tue Jul 03 2007 05:09 AM |
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Re: Wave nearing 40W Longitude
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Yeah i see what your talking about danielw. Although, that movement looks interesting.... Can it hold this far out in atl, and make it to the islands...(warmer water, etc.) or will it fall apart with all the dry air around it to the west and north?
http://www.sfwmd.gov/org/omd/ops/weather/plots/storm_96.gif
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danielw
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| (Moderator) |
| Tue Jul 03 2007 05:14 AM |
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Re: Wave nearing 40W Longitude
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Thanks, I was looking to see if some of the sites had picked up the model run.
That would leave it to crossing the "Hurricane Graveyard" of the Eastern Caribbean. As a 30 knots system I tend to think the Mountains of the Lesser Antilles would/ could 'knock the wind out of it".
Plenty of time to watch and see.
Or "Waiting...But Not Quite There Yet" as ED put it.
| cieldumort |
| (Moderator) |
| Tue Jul 03 2007 06:01 AM |
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Re: Wave nearing 40W Longitude
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Whatever can be said about its lack of chances, this is an impressive feature for this far out in the Atlantic this early in a season To put it plainly, this little one looks better to me than 95L and the curiosity I tracked for 12 hours or so a few days ago (the one to the SE of Bermuda) .. combined .. but not by much. Nor were those other two features anything to crow about, to begin with.
Still, now official 96L, currently centered near 9.5N and 38W as I type, is possibly about to enter a region of much-diminished shear (LINK) . This might bring up two possible scenarios as a result:
Scenario A) The low to moderate shear has helped flame the convection in an otherwise dry and stable environment, making some kind of FeS2-based concoction of what is really a benign 96L.. and as a result, the low shear environment merely exposes the Low for what it is: A weak low trying to make its way through a mostly dry, stable environment.
Scenario B) The low to moderate shear may or may not have helped fan the convection of 96L, but the Low itself is a little better-off than Scenario A would suggest. Entering the low shear region ahead leads to a marginally-favorable window for some "real" intensification, even tho this goes against the climo grain.
Given the structure of the surface or near-surface low, and the relatively juicy environ immediately encircling it, my guess is that Scenario A is not the more likely one. However, what I think might be more the impediment for 96L is the dry air just to its north and northwest, not to mention there's still likely to be lots and lots of killer SAL floating around north of 10N by the time it crosses that latitude, to be even more specific. (LINK).
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danielw
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| (Moderator) |
| Tue Jul 03 2007 06:03 AM |
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96L INVEST
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The Navy has posted the 96L INVEST on it's web site.
As of 0600Z or 2 AM EDT. First frame appears to be 0515Z.
96L Invest
| WeatherNLU |
| (Meteorologist) |
| Tue Jul 03 2007 07:48 AM |
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Re: 96L INVEST
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I tell ya, I just got back from work and I am tired but I am interested here. 96L surely looks like it's got it's stuff together to me. I want to see it persist through tomorrow, but looking at it on satellite tonight, I am seriously impressed. We shall see.
| allan |
| (Weather Master) |
| Tue Jul 03 2007 11:20 AM |
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Re: 96L INVEST
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Ok, lets not get too ahead of ourselves here
We all knew that this blow up would occur last night. Now it needs another boost to gain more power into a Tropical Deppression. Shear is very low on it's path but the reason why it's not already Chantal is 2 things.. SAL and it is still on the ITZS.. which makes a good circulation hard to get because it's all going in one flow, unless i'm wrong. We'll see what happens today, i'll give it a 60% of it becoming TD3. Even though we never ad TDs 1,2.. I think they will go to 3 right? lol
| Lamar-Plant City |
| (Storm Tracker) |
| Tue Jul 03 2007 01:22 PM |
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Re: 96L INVEST
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Are those just upper level features forming to the NE and SW of the 'center' or is it trying to form feeder bands? The thing looks better this am than it did when I hit the sack last night (about 12:45). It also has a little wobble back toward the due west or at least the convection does. No signs of it going 'poof' yet, although I have seen that happen enough before. Is it the 'Little Invest, that COULD"? I see all of the dry air to the north on the water vapor loop, but it seems to be tapping from the ITCZ to the south. Also a bit of outflow-looking features on that loop on the south side. Will be interesting to keep track of the next couple of days if it holds together.
| weather_wise911 |
| (Weather Hobbyist) |
| Tue Jul 03 2007 01:45 PM |
Re: 96L INVEST
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Looks like the convection just got blown south--displacing it from the low.
Any thoughts??
| allan |
| (Weather Master) |
| Tue Jul 03 2007 02:11 PM |
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Re: 96L INVEST
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Shear is only 5 knots where it is and headed.. as it enters the Carribean, it will enter around 5 to 10 perhaps 15 knots of windshear.. we'll have to see what happens today..
Unfounded comments removed. If meteorologists don't think that this wave is a TD, perhaps you can benefit by listening and learning from them, Lets not get too carried away with conjecture. Speculation without rationale belongs in the Forecast Lounge.)
| cieldumort |
| (Moderator) |
| Tue Jul 03 2007 02:30 PM |
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Re: Waiting...But Not Quite There Yet
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Some notable observations... Brings up the topic of the ITCZ, or, Intertropical Convergence Zone, some more. While the air tends to be flowing in one direction on its northern side in this hemisphere, "Monsoon Depressions" frequently form within the ITCZ - but with most never, ever becoming Tropical Depressions, and most never even earning as much as an Invest tag. Besides, 96L is simply not your average ITCZ depression, however. It's been more like a full-on wave that has transcended the ITCZ, all along. What is more, the ITCZ, by very definition, is a vorticity-rich environment. It is one very long trof of low pressure. An elongated nebula of cyclogenesis.
I do believe we are indeed viewing incipient banding features, which have been forming overnight. The internal structure of this Low is really not half-bad. Now if it can actually survive all the dry, stable air it has to contend with...
I suspect that it is not so much the wind that has "blown" the convection to the south, as much as it has been the effect of all that dry air to the humble cyclone's north that has squashed any real attempt to wrap deep convection all the way around. You can see this quite clearly in this morning's QuikSCAT pass, from 827Z, here
and this is still quite evident in the 1037Z TRMM pass
| ftlaudbob |
| (Storm Chaser) |
| Tue Jul 03 2007 03:38 PM |
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Re: Waiting...But Not Quite There Yet
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It is fairly clear at this point what is happening to this system.It is fighting with the dry air to the north,and as of this hour the dry air apperars to be winning.That doesn't mean things can't change down the road,But can it survive until then?I agree that if this were August or even late July there would be alot better chance of this system envolving into a cyclone. http://www.ssd.noaa.gov/goes/east/natl/loop-wv.html
| LoisCane |
| (Veteran Storm Chaser) |
| Tue Jul 03 2007 04:42 PM |
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Re: Waiting...But Not Quite There Yet
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thanks.. excellent description of what has been going on with this invest
looks much better on visible than other sats.. the banding signature is so evident
yet...the air is very dry
i dont think it was expected to do this well ... its getting further than i thought it would
keep watching
| Rich B |
| (British Meteorologist) |
| Tue Jul 03 2007 05:31 PM |
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Re: Waiting...But Not Quite There Yet
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Hi guys,
just been looking at 96L and quite surprised. Even NHC now suggest further development is possible, as per the latest TWO. SSD had it labeled as 'too weak' at 0545Z today, yet 6 hours later at 1145Z it was at T1.5/T1.5. Visible imagery shows decent banding, but this is mostly at low levels. The only deep convection is poorly organised in the southern semi-circle - probably due to dry air ingestion. If the system can mix this out, then it has a shot as it heads west through conditions which are not too forbidding. Certainly worth watching if you live in the Caribbean Islands!!
| LoisCane |
| (Veteran Storm Chaser) |
| Tue Jul 03 2007 07:41 PM |
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Re: Waiting...But Not Quite There Yet
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If this system makes it and holds together I would worry as sometimes it's the ones that persist in unfavorable conditions that come back to bite you later so to speak.
It is really riding the bottom of that high and we are talking very dry air... and the water vapor shows this well.
Also, you can see here how the convection keeps getting blown off to the sw and yet... it keeps spinning.
Giving it real points for tenacious.
http://www.ssd.noaa.gov/goes/east/catl/loop-wv.html
| HURRICANELONNY |
| (Weather Guru) |
| Tue Jul 03 2007 08:01 PM |
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Re: Waiting...But Not Quite There Yet
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At least there is moisture in the mid levels that probably will keep the LLC going. As long as it doesn't hit heavy shear and from what others have been posting. It looks good.
http://www.ssd.noaa.gov/PS/TROP/DATA/RT/eatl-wv-loop.html
| Lamar-Plant City |
| (Storm Tracker) |
| Tue Jul 03 2007 10:21 PM |
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Re: Waiting...But Not Quite There Yet
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Did get pretty ragged during daylight today, however, the latest water vapor loop seems to show another blowup of convection forming on the north side of this thing.. It sure could go 'poof' at any moment, but it looks like it is going to hang on until tomorrow at least. It doesn't look like it is going to give up easily. I know several have said it would have to get away from the ITCZ before it could develop, but with dry air to the north that could kill it, could it survive because it is staying connected to the moister area in the ITCZ?
| Hugh |
| (Senior Storm Chaser) |
| Wed Jul 04 2007 01:29 AM |
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Re: Waiting...But Not Quite There Yet
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I don't know what to make of 96L. The 5pm TWO indicated that it was less organized (not in so many words) than earlier in the day, but right now, it looks very much like a tropical depression, to my eyes anyway. It's not a storm, but it has a rotation, and convection near the rotation. There's some nice banding features, too, for a storm this far out to see on July 3rd. If it were 2005, I would have guessed they would have pulled the trigger already, but the new crew at the NHC seems less inclined to throw up advisories on things of this nature.
Will it survive a substantial trek across the Atlantic and enter the Hurricane Graveyard (AKA the eastern Caribbean)? Time will tell.
(Speculation without supporting rationale belongs in the Forecast Lounge.)
| Clark |
| (Meteorologist) |
| Wed Jul 04 2007 01:45 AM |
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Re: Waiting...But Not Quite There Yet
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The diurnal convective max has apparently brought 96L perking to life tonight, looking like a bonafide tropical depression of sorts. It's not there yet, and NHC tends to like to wait a little bit with storms well out at sea to see how well they maintain their organization over time, but if current trends continue into the afternoon hours tomorrow -- I think we might just get a classified system out of this one after all. It's still ingesting some stable air at low levels, keeping the overall organization from being too impressive and partially helping keep the cloud tops from getting too cold, but other than that factor there's not a whole lot against slow organization over the next few days.
Basically -- by midday tomorrow, we're going to know if it's going to take that next step and become something interesting...or if it is just going to pulse up and down on into the Caribbean Sea. Something to watch, to say the least.
| Hugh |
| (Senior Storm Chaser) |
| Wed Jul 04 2007 02:07 AM |
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Re: Waiting...But Not Quite There Yet
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Clark.. any "gut feeling" on a medium to long range track that this thing might take if it does develop? I know, that's impossible at this point, but... I'm going on a trip in a few weeks, plus my boss is off on his annual trek to Port St. Joe. So the deck is sort of stacked against us.
Are there any troughs that are likely to push whatever comes out of this thing out into the central Atlantic?
(In the future if you direct a question to a particular individual, please use the PM capability rather than a post.)
| HanKFranK |
| (User) |
| Wed Jul 04 2007 02:12 AM |
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Re: Waiting...But Not Quite There Yet
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it's gotten closer to being something. i could see that it was turning some the other night.. now it's turning pretty good with some banding features and a decent vortex that is peeking between convective bursts. two things are going to work against it--the very dry mid-tropospheric layer that it will encounter for the next 2-3 days, and it's forward speed. the trades aren't exactly creeping along, and it seems like about half of the july depressions that form east of the islands hitch a ride on one and keep racing along until they eviscerate themselves on shear or just simply open up into waves again. it does look like it'll make depression status, but its long term prognosis is still a unfavorable unless it can make it to the islands this weekend at a passable forward speed (i.e. less than 18 knots or so). don't expect it could get there with a great deal of intensity, but a storm in the caribbean this weekend would be a whole different story. synoptic pattern would probably recurve it east of the u.s., but that's highly speculative (a lot has to happen just to get to that juncture).
HF 0211z04july
| cieldumort |
| (Moderator) |
| Wed Jul 04 2007 03:44 AM |
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Re: Waiting...But Not Quite There Yet
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We've got a TCFA up on 96L.
Can't say I'm surprised. While convection has been half-hearted because of all that dry, stable air to its north, the low level vortex is a tight little bugger, and what convection has been persistent (southern semi-circle) has really been rather persistent. And now, a thin ring of somewhat deep convection appears to have fully encircled the llc.
(Link)
TCFA-Tropical Cyclone Formation Alert ~danielw
| Storm Hunter |
| (Veteran Storm Chaser) |
| Wed Jul 04 2007 03:58 AM |
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Re: Waiting...But Not Quite There Yet
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Just saw that too.. It was issued at 040000z. So it just came out. And i just happen to look at the latest sat. Looks like the low level center may be exposed some now in the last few hours. The storms seem to be blowing off to the sw of what i think is the center. Navy has it at 10.4n 40.7w at 040000z. opps... here's msg!
(Off-topic material removed. Please don't mix your meteorological metaphors )
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danielw
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| (Moderator) |
| Wed Jul 04 2007 04:11 AM |
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96L Preliminary model
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00Z Model test run out to 120 hours-5 days is indicating 96L somewhere near the Northern Lesser Antilles.
This run would place the system in the Leeward Islands, north of Martinique.
While the 18Z GFDL model dissipates the system at +66 hours. Near 10N/ 48W.
Current Model Test Plot
Jonathan Vigh's Tropical Cyclone Model Guidance
| WeatherNLU |
| (Meteorologist) |
| Wed Jul 04 2007 05:18 AM |
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Re: Waiting...But Not Quite There Yet
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There's no doubt in my mind it's a Tropical Depression already. If they had the ability to get out there right now, they would find a closed low with sustained winds of 25 mph or greater in my opinion. The thing is it's heading towards the Caribbean which is about as unfavorable as can be right now for development.
Whether or not it's gets the TD classification from the NHC is up in the air, but using the basic definition of a Tropical Depression, it's already there.
Just my 2 cents.
| dem05 |
| (User) |
| Wed Jul 04 2007 06:04 AM |
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Re: Waiting...But Not Quite There Yet
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Quote:
I know several have said it would have to get away from the ITCZ before it could develop
I am revisiting an earlier quote here...Well, it is not necesarily true that the system would have to break free of the ITCZ. Remeber, the ITCZ is a convergance of the trades, this creates lift fort-storms, and also can help these systems in getting their spin. So the ITCZ is actually one of the birthplaces for tropical activity. With that said, if a wave looses it's cyclonic appearance and stretches from east to west in an ovular pattern, this is likely the beginning of the end for the potential development of that feature...as the system would be regenerating into the overall ITCZ signature, this most often happens during periods of strong trade winds, which allow the cyclone to elongate.
As for 96L...it's not getting any stronger tonight, but it shows no signs of elongating (weakening) either. In fact, the circulation pattern seems very symetrical, even though the thunderstorms are not. Give it some more time to hang in there and we may be looking at a TD tomorrow or on Thursday...Clark said the right stuff again tonight, right after his post, some of the activity went poof, but the thunderstorms to the south have resurged and the tops are cooler than before. So he is on track. To back him up further, I'd say that if it is gonna develop, expect up and down surges from hour to hour (hours to hours long), with an overall trend toward improved thunderstorm activity and slow development over the long hual. If you are looking for quick development, or quick sure fire trigger identifiers to indicate the development or dissipation of 96L, I do not think you are gonna see that from satellite frame to satellite frame. This is tennacious enough to last this long, it hasn't faded yet, and likely will not spin down quickly based on these facts...More opportunities for slow development exist in the next several days, so stay tuned, this may become a TD at some point.
| nc_tropical_wx79 |
| (Weather Guru) |
| Wed Jul 04 2007 10:38 AM |
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Re: Waiting...But Not Quite There Yet
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Does 96L expanding in area mean anything (like weakening or even strengthening?). Just in my opinion it looks like 96L has grown a little bit larger.
| allan |
| (Weather Master) |
| Wed Jul 04 2007 01:48 PM |
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Re: Waiting...But Not Quite There Yet
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Not to bash them, but wunderground bloggers have given up up 96L this morning.. I still think it's something to watch and of course the bloggers in there are just ordinary people, not Mets. Yes, it has weakened due to dry air and daytime skies, no, it will not "poof" like they are pushing it will do now in 48 hours. The window is still open in my opinion.
| nc_tropical_wx79 |
| (Weather Guru) |
| Wed Jul 04 2007 01:55 PM |
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Re: Waiting...But Not Quite There Yet
|
i agree with you on the part that wunderground bloggers are normal people because I'm a normal person not a Met(at least not til I graduate in 3 more yrs.) but it is Dr. masters himself who said since yesterday when 96L was first established that it will not make TD status and he as of right now says it won't make TD status due to dry air winning over 96L and shear being too high once it passes the Antilles(sp?). So far this morning and all day yesterday he's been right because 96L hasn't made TD or TS yet and dry air has been winning over 96L and it's center been exposed.
| nc_tropical_wx79 |
| (Weather Guru) |
| Wed Jul 04 2007 01:57 PM |
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Re: Waiting...But Not Quite There Yet
|
I'm not arguing with you or saying you're bashing wunderground bloggers I'm just being more clear on what I've said on my part. I hope I didn't and apologize if you've been offended.
Take up the Wunderground stuff with PM's, not here.
| weather_wise911 |
| (Weather Hobbyist) |
| Wed Jul 04 2007 02:39 PM |
|
96L Dead??
|
Certainly looks like 96L is dead & gone. Convections is completely displaced from the center, and the dry air just keeps getting wrapped into the circulation. My opinion... this was a T.D. yesterday... now, the chances of it becoming such appear slim to none.
| CaneTrackerInSoFl |
| (Storm Tracker) |
| Wed Jul 04 2007 03:07 PM |
|
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Re: 96L Dead??
|
I wouldn't call it dead or gone by any stretch of the imagination. They convection is certainly not completely displaced from the center of circulation. In fact, this is something thats gone on with it the past few days. As soon as we think its dead, the convection flares up again.
Plus, the low level circulation is still very vigorous.
| Hugh |
| (Senior Storm Chaser) |
| Wed Jul 04 2007 03:23 PM |
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Re: 96L Dead??
|
Quote:
Plus, the low level circulation is still very vigorous.
My thoughts exactly. There is obviously alot of shear that is preventing the system from developing into a bonifide tropical depression, but it has not given up trying. In order for it to actually develop, though, conditions will have to greatly improve in the eastern Caribbean... unless it some survives in its current form (without increasing or decreasing in organization) until it makes it all the way into the western Caribbean. I don't know if conditions will be any better for development there, but at least historically, the western Caribbean is a better place for a tropical disturbance to be than the central Atlantic or eastern Caribbean this time of year.
| ftlaudbob |
| (Storm Chaser) |
| Wed Jul 04 2007 04:52 PM |
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Re: 96L Dead??
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The shear is low in that area,it is the dry air that is the reason it has not developed more.But I'll tell you what,This is a tough system it is still hanging on.
| Hugh |
| (Senior Storm Chaser) |
| Wed Jul 04 2007 08:28 PM |
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Re: 96L Dead??
|
Looks sheared to me - especially looking at the water vapor loop, which shows all of the moisture getting pushed to the south. The dry air certainly is a bigger problem, though, you're right. On the WV loop I can clearly see the circulation... except instead of dark blue (which would be indicative of heavy moisture) the LLC is showing up brown! It's a very strange sight - looks like there is a channel going just shouth of the system, that is a barrier between the incredibly dry air to the north (where the circulation is) and the moisture to the south.
Right now for me its an interesting thing to study, but far from a tropical cyclone (further than earlier today)
ETA: since the sun set over the system, a tiny batch of convection has fired near the LLC. Certainly nowhere close to enough to pull the trigger, but it's interesting.
| CaneTrackerInSoFl |
| (Storm Tracker) |
| Thu Jul 05 2007 04:48 AM |
| Attachment |
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Re: 96L Dead??
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The convection continues to persist. It just won't die. In fact, as of the last satellite picture, convection has been trying to pop up on the northern side of the system.
And on the water vapor imagery, it appears the dry air is just weakening slightly to the north of the system:
WARNING TIME SENSITIVE
http://www.ssd.noaa.gov/goes/east/catl/loop-wv.html
| cieldumort |
| (Moderator) |
| Thu Jul 05 2007 05:23 AM |
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Re: 96L Dead??
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These little flareups - sort of gives new meaning to *pulse* convection
Quick observations - dry air is now -really- beginning to fill in around the Low on just about all sides but the south, with more dry air than any one cyclone could choke on north of 11N between roughly 37W and the longitude of the Invest. But worse yet for it.. the dry air now sinks all the way down to about the equator in its path immediately ahead. This alone makes the environment simply inhospitable for anything but slow development, at best. (Link)
Now introduce increasing wind shear, also just up ahead .. now approaching greater than 30 knots in spots.. and still rising (Link).
At a forward speed of roughly 12 knots, give or take, 96L may have another day and a half of marginally favorable environmental conditions (and that may be describing them generously) to pull something "significant" off - in the near term - However, given the tenacity of the Low, this may not be entirely comforting if it should somehow retain some semblance of itself, miss the opportunity to deflect, only to find a sweet spot somewhere else sometime in the future, and closer to the point of a land-lock somewhere. Given the current steering pattern, that possibility might be of some future concern for locations from Central America to Louisiana.
Fortunately, given the climatology for this point in the season, the number of ULLs still diving down into and TUTTs forming in the GOM and Caribbean, the above situation does not seem very likely. But, it's probably one to keep in mind for however long the Invest is out there in some recognizable form and stature.
1AM Edit (1 AM Central time folks)
I'm actually starting to think my hat might be off to 96L overnight.
| dem05 |
| (User) |
| Thu Jul 05 2007 06:23 AM |
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Re: 96L Dead??
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In general, 96L is definately going through another pulse. Saw one late last night yesterday and another that was several hours earlier yesterday afternoon. I'm a little hesitant to say this is a development trend since these occurances happened yesterday. Wouldwanttogetmyfingers chomped bymother nature! LOL. With that said, it is interesting to note that thunderstorms are buliding on the north and west sides of the circulation...as well as the south side...this is a first in the last 48 hours and the wind structure of 96L remains symentrical. If the storms do not go poof, then we are onto some possible additional development.
Water Vapor, yes..lots of dry air is a continueing challenge, but this evenings loops do suggest that the atmosphere ahead of the systemis moistening up somewhat, and the area ahead of the system is approaching the current moisture levels of the evironment around 96L. WIll be interested to see if the moisture builds up a bit more ahead of 96L. On a final note, the shear producing upper level low, which was referenced in the NOON CFHC Update at 14Nand 60W, which is the area that would threaten to produce shear in about two days...has not decided to move north as the model shave suggested...instead, it is currently moving west. If this continues, this shear may Cieldumort has shown us may stay out ahead of the system and 96L environment beyond two days may not be that hostile afterall. But Cieldumort is right, the shear as shown in his map is currently increasing ahead of the system. If the Upper Low pauses in it's westerly track, or the shear zone does not progress westward ahead of the system...this will be a development show stopper. I know that I will be very curious to see if the westward movement (versus Northerly movement) of the ULL persists. This could be very important to any possible future development (Day 2 andbeyond).
Water Vapor Link of the Central Atlantic: http://www.ssd.noaa.gov/goes/east/catl/loop-wv.html
| cieldumort |
| (Moderator) |
| Thu Jul 05 2007 06:47 AM |
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Re: 96L Dead??
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I am bought-in. I posted less than two hours ago on the difficult environment that 96L has been struggling in. I still see that 96 is still in that generally less-than-friendly part of the world... and for all the reasons I outlined above.. but I am not the first, nor the last, to comment on this bugger's penchant for holding on and fighting back. As has often been stated here and elsewhere... it's often those tenacious ones that we really ought to be wary of, as they can, and have been known to, fight just about everything back, and deliver upside surprises - not to mention toy with the forecast tracks.
So, if this most recent trend of wrapping convection all the way around the center of the vortex continues - and I will qualify this with saying we have seen this with 96L twice before now, actually - I'll give it the Third Times the Charm benefit of the doubt, and agree that it is probably on its way to earn more than honorable mention.
| madmumbler |
| (Storm Tracker) |
| Thu Jul 05 2007 01:35 PM |
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Re: 96L Dead??
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As of right now (9:30am) it almost looks like it's falling apart again when I look at the water vapor loop and the visible loop on the floater.
Am I looking at that right or am I missing something?
| weather_wise911 |
| (Weather Hobbyist) |
| Thu Jul 05 2007 02:21 PM |
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Re: 96L Dead??
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You're seeing it right--there is hardly any convection...... and I doubt there will be anything more than "flare-ups" every few hours.
| audienceofone |
| (Verified CFHC User) |
| Thu Jul 05 2007 02:27 PM |
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Re: 96L Dead??
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I think you're seeing it right. Seems to be losing even more convection today and with an increasingly hostile environment predicted in the next day or two (and the already dry air to the north), chances for development are looking very slim. Maybe with something a little stronger today it could outlast the upper level environment it will be facing, but the way it currently looks I wouldn't bank on it.
edit: you beat me to it weather-wise =) i need to learn to type faster
| Bloodstar |
| (Moderator) |
| Thu Jul 05 2007 08:26 PM |
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Re: 96L Dead??
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Well, 96L is skeletal, but with pulsing convection, and moving towards warmer waters, there's always that chance that it could ramp up into something quickly. The LLC seems healthy enough, though some of the visible imagery seemed to imply a really sharp trough rather than a full circulation (seemed to be lacking on the south east side a bit). Interestingly enough the storm looks much better when viewed on a wider scale, then the structure really stands out. But by me saying something, it's the kiss of death for development. *grins*
Of passing interest is the sloppy system right off the florida/georgia coast. If it were to slight a little out to sea, it might get some organization together. as it is, I think it's drifting west into land, so that's probably a non starter.
Not much else to look at, So far a quiet start to July. I'd say things had been slow, but we have had 2 systems already, hard to believe that. *heh*
(Forecast Lounge material removed)
| HanKFranK |
| (User) |
| Thu Jul 05 2007 11:53 PM |
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Re: 96L Dead??
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there it goes again, popping off more convection this evening. the system has gradually lost convection, re-firing more (but a little bit less every time) steadily over the last couple of days. tonight it may have reversed that slightly. the tight vortex tracking just north of due west along 11n is just as easy to pick out as ever. there does appear to be more vertical shear than before, but perhaps the environment is becoming a bit more moist and unstable. the balance of odds is still against, but that little low-level swirl has kept intact fairly well (i'd attribute most of that to it not racing along at breakneck speed--it's stayed around 15mph). that is the sort of feature that would be a tropical cyclone if you tossed a good flareup of deep convection over it for a 12hr period. as things stand that still probably won't happen. it just isn't gone yet.
the nhc is finally mentioning the mess near florida. that sort of thing would be raising all sorts of eyebrows were it over water and threatening the coast.. but it's over land and likely to drift off. a good supply of shortwave energy passing to the north over the next few days should act to work it offshore and out. there's enough shear that development remains unlikely.
long range modeling showing the ridging in the atlantic building further westward, and with the arrival of the mjo wave later this month a strong possibility i'd reckon we'll see some development before too much time passes.
HF 2353z05july
|
danielw
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| (Moderator) |
| Fri Jul 06 2007 01:54 AM |
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Re: 96L Dead??
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Even though the convection is limited with this system.
The Test Model runs are still taking the system into the Caribbean Sea.
http://www.sfwmd.gov/org/omd/ops/weather/plots/storm_96.gif
Through 120 hours-5 days. The models still maintain the system below 39 knots, or Tropical Storm strength.
The vortice signature of this system is tenacious at the least. Crossing the Caribbean Sea below Tropical Storm strength would limit the potential for shear, and other parameters to interrupt the atmospheric processes. In other words. We would be better off if the storm would develop to some degree.
With the SSTs getting warmer by the day. The current model run would put 96L in a very favorable area in 5 days. With respect to the lower levels and surface conditions that are currently in the Western Caribbean.
Development, should that occur, in the Western Caribbean would/ could mean an almost certain threat to the GOM Coasts. From Brownsville,TX to Key West,FL and the Eastern Florida Coasts in the long term.
|
Ed Dunham
|
| (Former Meteorologist & CFHC Forum Moderator (Ed Passed Away on May 14, 2017)) |
| Fri Jul 06 2007 02:16 AM |
|
One Other Factor...
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...to consider. Take a look at the Water Vapor image:
NOAA Central Atlantic Water Vapor
You have to look closely, but dry air surrounds the system - and thats a large swath of bleached-bone-dry air that 96L is heading into. Models notwithstanding, it may be difficult to find any remnant of this system before it even gets to the Caribbean Sea. The upper low is going to keep the dry air in place for quite a few days.
ED
| scottsvb |
| (Weather Master) |
| Fri Jul 06 2007 03:06 AM |
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Re: One Other Factor...
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Alot are talking about the system east of the islands but the chances of this developing is less then 10%. Dry air is surrounding this wave. Chance might go above 10% once it gets to the sw carribean but really to be honest..there is nothing out there for the next 3-5 days.
| cieldumort |
| (Moderator) |
| Fri Jul 06 2007 07:20 AM |
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Re: Waiting...But Not Quite There Yet
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Been interested in watching our -new- Invest just offshore?
There has been a little speculation about the low over Florida sliding offshore and sparking the interest of NHC. Yesterday a weak coc moved offshore of roughly Jacksonville, best I can tell, and has now begun acquiring some deep convection. Pressures are still fairly high, but falling a little bit, waters are warm, shear is under 30 knots, and unlike the environment in and around 96L, the air is not at all bone dry.
(Invest Floater Link)
| Bloodstar |
| (Moderator) |
| Fri Jul 06 2007 08:04 AM |
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Re: Waiting...But Not Quite There Yet
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Go figure, it drifted east ... not west. *laughs*
it's sloppy and sheared... but certainly could be interesting to watch tomorrow.
96 is also getting sheared, but still seems to be holding a pretty distinct (as best as one can tell at night) circulation.
Neither system has their act together, though the florida system is putting out some good convection about 50 - 75 miles from the circulation center.
I still think the odds are low for the next 24 hours, but start to go up if the systems hang together. the environment should get better, but for both systems they're not going to have super favorable environments to flourish. at least for another 48 hours.
| madmumbler |
| (Storm Tracker) |
| Fri Jul 06 2007 12:40 PM |
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Re: Waiting...But Not Quite There Yet
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Quote:
Been interested in watching our -new- Invest just offshore?
Holy *&^%. I looked at the water vapor loop.
BUT -- that's heading out to the open Atlantic to become a fish spinner regardless, right? Whether or not (most likely not) it develops into anything of substance, it's moving out and except for some well-needed rain, it's not bringing us anything...right?
| Hugh |
| (Senior Storm Chaser) |
| Fri Jul 06 2007 01:20 PM |
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Re: Waiting...But Not Quite There Yet
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Quote:
Holy *&^%. I looked at the water vapor loop.
BUT -- that's heading out to the open Atlantic to become a fish spinner regardless, right? Whether or not (most likely not) it develops into anything of substance, it's moving out and except for some well-needed rain, it's not bringing us anything...right?
Actually it appears to me that it is heading southeast. Still out ot sea ultimately. Bermuda is a more likely target in the unlikely even that something forms from it.
| doug |
| (Weather Analyst) |
| Fri Jul 06 2007 03:25 PM |
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Re: Waiting...But Not Quite There Yet
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The 11:30 a.m. TWD, and TWO say it all on the low off Jax.
| HanKFranK |
| (User) |
| Sun Jul 08 2007 08:25 PM |
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blah
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as ed mentioned in the his short update today--the action is still a basin over. the long range gfs isn't showing anything to write home about on our side of the pond, still. they've obviously tweaked its algorithm for the parameters that govern tropical cyclogenesis... the gung-ho, every wave a storm gfs we've seen at times isn't on the job right now. until the storms show up again we won't know whether it's prognosticating better or just blinded. might be the former, ya know.
even without faith anything will happen, might be interesting to see what our erstwhile texas system does when it drifts off the southeast coast. the weak non-tropical low with the slightly frontal appearance that has been drifting eastward since leaving texas to dry out late last week is now over east-central alabama, meandering east. it's sort of like the july version of one of those winter-time storms that teases my neck of the woods with frozen precip, only about 40-50 degrees too warm. be funny if it reformed offshore like shortwave energy jumping from a mature frontal low to the triple point or a coastal lee trough. it ought to be over the atlantic coastal plain this time tomorrow. i vote it freak of the week.
stuff is trying to go in the pacific right now. big typhoon in the works east of the phillipines (12z euro had it smashing into kyushu next weekend as a big-ol mutha). closer in there are a couple/three things in the eastpac trying to fester. mjo doesn't always move in a neat, orderly wave and cause things to happen in our basin after tripping off the pacific, but more often than not it does have an effect. over the next week we ought to see the atlantic look more lively. maybe we'll get something by next weekend or later.
HF 2025z08july
| Lamar-Plant City |
| (Storm Tracker) |
| Mon Jul 09 2007 12:23 AM |
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Re: blah
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Everything may be quiet now, but let me just speak from first-hand experience....if anything DOES get going in the GOM, there is PLENTY of heat in the water for it. Went to Ft Desoto park yesterday (the extreme South end of Pinellas County along the channel) and the water was almost uncomfortably warm. It HAD to be in the 85 degree range, warmer right along the shore, but it didn't cool much 100 yards from shore either. It was like swimming in a warm bathtub. Looking at the buoys bears this out. LOTS of heat energy out there and now a few days of relatively clear skies and scorching hot temps will only increase this. Only 20-30 POPs in Central Fla this week so the heat is on as is showing on the SSTs for the GOM and here ( http://www.esl.lsu.edu/webpics/CMI-GOES/GOES-comps/WEEKCOMP/latest_week_coded.gif) as well.
| Ed in Va |
| (Weather Master) |
| Tue Jul 10 2007 03:24 PM |
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Re: blah
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Couple of blow-ups off the SE coast and north of SA...any possibilites with these?
| nc_tropical_wx79 |
| (Weather Guru) |
| Tue Jul 10 2007 04:49 PM |
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Re: blah
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Nothing of any major consequence happening down in the tropics today like the past few days. There's some convection I notice going on down near Central
America well it's a tropical wave thats making it's way west. It has cyclonic turning in the mid levels but the problem is that this wave should find it's self from the Atlantic into the Pacific in the time frame of Wednesday night maybe Friday at the latest. Last but not least close to home for me there's an area of convection off of NC. Just my 2 cents but this convection may be just convection kicked up because of the diffluent flow between the ridge and a departing trough. Fortunately or unfortunately depending on how you look at it there's nothing going on yet down in the tropics yet.
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danielw
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| (Moderator) |
| Fri Jul 13 2007 04:46 AM |
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Long Range Forecast
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This is an excerpt of a long range forecast from earlier today. The forecasters are giving notice to the run to run continuity of the GEM Ensemble models. But it appears that the GEM is an outlier. Being the only Model with this solution, and the solution is being cast aside for that reason. My interpretation of the following excerpt. Stay tuned!
PRELIMINARY EXTENDED FORECAST DISCUSSION
NWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD
932 AM EDT THU JUL 12 2007
VALID 12Z MON JUL 16 2007 - 12Z THU JUL 19 2007
...GEM GLOBAL STILL INSISTS ON BRINGING A TROPICAL SYS INTO SRN FL AT THE END OF THE PD... A SOLUTION REJECTED AS AN OUTLIER DESPITE THAT MODELS CONSISTENCY WITH THIS SYSTEM.
http://www.hpc.ncep.noaa.gov/preepd/preepd.html
| Tropics Guy |
| (Storm Tracker) |
| Fri Jul 13 2007 01:52 PM |
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Re: Long Range Forecast
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Yesterdays run of the the CMC shows a developed low approaching S Florida in about 144 hrs.
http://moe.met.fsu.edu/cgi-bin/cmctc2.cg...;hour=Animation
TG
| cchsweatherman |
| (Weather Watcher) |
| Fri Jul 13 2007 02:06 PM |
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Re: Long Range Forecast
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It is looking very interesting now in the tropics as an arriving MJO and a developing La Nina are arriving at the perfect time to potentially have a breakout of tropical activity right in the heart of hurricane season. The CMC model caught my eye yet alone my attention as it appears as if these tropical waves are continually coming off Africa at a higher frequency and appear to be stronger every time. I have a "gut feeling" as Michael Chertoff would say, that we are now in the calm before the storm as the ingredients are now just setting into place. Buckle your seatbelts boys. We are in for a bumpy ride.
| Storm Hunter |
| (Veteran Storm Chaser) |
| Sat Jul 14 2007 08:03 AM |
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Re: Long Range Forecast
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CMC is moving more left... aka.. more of a typical Carribean/GOM JULY system... around the high... the next two to three days might be interesting.... i am not seeing any other globals lookin the same just yet, but few more days will tell.
cmc 2007071400
more to come in next few days...
| Robert |
| (Weather Analyst) |
| Sat Jul 14 2007 04:45 PM |
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12n 32w
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Big wave off afric wsw of cape verde island looking interesting this morning could be what the models are picking up on for the end of this coming week.
| Robert |
| (Weather Analyst) |
| Sat Jul 14 2007 04:50 PM |
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Re: 12n 32w
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Not focusing on the center of it but the wave as whole it seems to take up almost half the atlantic.
| scottsvb |
| (Weather Master) |
| Sat Jul 14 2007 05:44 PM |
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Re: 12n 32w
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Right now..nothing appears to be of intrest for the next several days. Maybe in a week or 2 we might get something off Africa but right now..pressures are high and there is alot of dry air pushed wayyy to south to near 10dgN keeping the ITZ south of there. CMC is a outliner model usually and I wouldnt give it more then 10% chance.
| Storm Hunter |
| (Veteran Storm Chaser) |
| Sat Jul 14 2007 06:17 PM |
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Re: 12n 32w
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looks to me that the CMC is working the tropical wave that is about to enter the islands..... takes it through the carb. on a westward track.... 12z run today is a little more agressive. Not seeing much other global support right now... Just something to watch... Upper Level winds in carb. are a little hostile right now...
| Robert |
| (Weather Analyst) |
| Sat Jul 14 2007 08:54 PM |
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Re: Waiting...But Not Quite There Yet
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In my expirience i notice when a model goes bisurk on a strong wave wich the one at 10 and 58 is, its precluder to an even stronger one that usually doesent fall apart very easily and makes it across to become a storm. Honestly i can see the front running wave coming north into florida this week enhancing the trough off north carolina and developing and moving out leaving the big wave behind it to come under neath and develop into possibly are first hurricane in the gulf this season. this due to fact that once the trough develops and moves out it will be replaced by a ridge with almost perfect conditions across the carribean.
| Robert |
| (Weather Analyst) |
| Sat Jul 14 2007 09:18 PM |
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Re: Waiting...But Not Quite There Yet
|
000
AXNT20 KNHC 141749
TWDAT
TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
205 PM EDT SAT JUL 14 2007
EASTERN ATLANTIC TROPICAL WAVE IS ALONG 27W SOUTH OF 18N MOVING
WEST 15 KT. VISIBLE SATELLITE IMAGERY INDICATES THAT THIS IS A
FAIRLY LARGE WAVE WITH TURNING IN THE STRATOCUMULUS FIELD NOTED
BETWEEN 20W AND 40W. SCATTERED MODERATE TO STRONG CONVECTION WAS
NOTED ALONG THE ITCZ FROM 7N TO 9N BETWEEN 27W AND 32W
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danielw
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| (Moderator) |
| Sun Jul 15 2007 09:02 AM |
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CMC Model
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For the 5th or 6th straight run. The CMC is still forecasting a Tropical System in the area of the Florida Straits moving westward over the next week.
At 96 hours the CMC take the system to a landfall on the Mid-Louisiana Coast near Terrebone Bay.
96hour 850mb Vorticity CMC Model
Other Model Runs here:
http://moe.met.fsu.edu/tcgengifs/
At this time there is no other mention of this possible system in the various NCEP Discussions.
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danielw
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| (Moderator) |
| Sun Jul 15 2007 12:11 PM |
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Heads Up??
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Current mid to upper level low (TUTT?) located just to the north of Puerto Rico. Is moving SW toward the Turks, Caicos and Acklin Islands. 7 hour wv loop indicates the center of the system should be near 22.0N/ 70.0W at 11Z.
Wv Loop-Puerto Rico Area
GOES Puerto Rico Section
A quick check of the models for the 12Z time frame.
NOGAPS 850mb Vorticity for 06Z 071507
Notice: The NOGAPS position is about 6 hours behind the current position.
The CMC, GFS, UKMET and NOGAPS are all indcating a small 850mb vortice in the area north of Puerto Rico at this time.
http://moe.met.fsu.edu/tcgengifs/
All of the above positions were on the 071507 0000Z model run.
CMC at 72 hrs...Mid GOM South of Pensacola
GFS at 72 hrs...Vortice just NE of the Bahamas
NOGAPS at 72 hrs...Small wave near the TX Coast
UKMET at 72hrs...Wave in the Western GOM
All are from still images at 72 hours. And I did not view the loops for continuity.
| allan |
| (Weather Master) |
| Sun Jul 15 2007 01:06 PM |
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Re: Heads Up??
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That's what I was trying to point out but I got corrected. UKMET had at least a wave with what the CMC was trying to make a TS out of. Now on the 0z runs, the CMC has dowgraded the storm to only a deppression in the GOM. It is something to watch, and know that anything can happen in the weather, we can't control it. So lets see what the next few runs show. That wave that models are hinting at is now near the Islands and has gained some convection but I expect that to decrease as shear right over it is 35-40 knots. Though as it continues to move, the shear will slowly decrease and maybe the CMC has a point like it did with Alberto (2006), Andrea, and Barry.
| BLTizzle |
| (Verified CFHC User) |
| Sun Jul 15 2007 07:28 PM |
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Re: Heads Up??
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all of the 12Z runs don't have anything now except for the CMC which has a small low just north of puerto rico at 144 hours.
| LoisCane |
| (Veteran Storm Chaser) |
| Mon Jul 16 2007 02:59 PM |
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Re: Heads Up??
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nice twist there... i dont think cmc is predicting anything today.. getting tired of looking lol
interesting twist at the edge of cuba there where it kept forming something the last few days
http://www.ssd.noaa.gov/goes/east/pr/loop-vis.html
like gitmo doing weather modification? seriously, is anything going on down there
the area looks way too unfriendly and can't imagine an ULL could work it's way down and the wave looks sheared
any thoughts, im happy to read them so give me some thoughts please
| cieldumort |
| (Moderator) |
| Mon Jul 16 2007 11:09 PM |
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Re: Heads Up??
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Might be -barely- more interesting along or near Texas the next few days, as two waves could approach the area. As mentioned, there is that one just to the east of that hungry ULL which has been eating it for lunch, and it appears something could creep up the eastern coast of Mexico, or also possibly form out in the middle of the GOM.
The outlier CMC has withdrawn its forecast of a tropical storm in the GOM this week, but still the NAM is now hinting that such a wave could produce some inclement weather out this way (along or near Texas). Caught the eye of our area NWSFO this afternoon, and thus was mentioned in the last Area Forecast Discussion, here. Thinking is, any window for this wave to initiate or help promote tropical cyclone formation will be rather limited, if at all. Might be more interesting should the ULL over Cuba weaken some, and begin working with, rather than against, the wave out there.
As noted elsewhere, SSTs in the western Caribbean and central GOM are quite warm, and to a significant depth. Should favorable atmospherics come together in that general region, there would be more than sufficient quantities of warm water to help fuel a deep warm core system out there.
| OUSHAWN |
| (Weather Guru) |
| Tue Jul 17 2007 03:29 PM |
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Re: Heads Up??
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Is it me or is there just a big mess in the BOC right now. Doesn't look like anything is organized but looking at the visible there might be a slight turning just north of the mexican coast in the southern most part of the BOC. Still can't really tell for sure,however. I know there has been some models trying to bring "something" to the Texas coast so I guess we'll have to wait and see.
Shawn
| Robert |
| (Weather Analyst) |
| Tue Jul 17 2007 04:17 PM |
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Re: Waiting...But Not Quite There Yet
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does no one notice the circulation on the north coast of hati domincan republic probally wont hold togethor but this is the same wave at the same time fram the cmc was forcasting have come in to florida.
| Robert |
| (Weather Analyst) |
| Tue Jul 17 2007 04:38 PM |
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north of hati
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the circualtion is samll and is between the upper level low to ne and its sw. it is under a small ridge of high pressure directly north of it that flows into south florida?
(Off-topic material removed.)
| Beach |
| (Weather Guru) |
| Tue Jul 17 2007 05:26 PM |
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East of Florida
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I was looking at:
http://www.ssd.noaa.gov/goes/east/watl/loop-wv.html
If you look out directly East of Central Florida (about 1300 miles) somewhere close to 63W 30N there seems to be circulation stacked up on all 3 scales, HDW-Low, Med, High
according to the "flags"
Does anyone else concur?
| nc_tropical_wx79 |
| (Weather Guru) |
| Tue Jul 17 2007 06:51 PM |
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Re: East of Florida
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I concur with you but don't think anything will come of this tropical cyclone wise
(Please remember to include your rationale as to why you believe that nothing will come of it - otherwise its just a one-line post that could have been sent as a PM.)
| cieldumort |
| (Moderator) |
| Tue Jul 17 2007 07:25 PM |
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Re: Waiting...But Not Quite There Yet
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Lots of talk about the mess in the western Gulf of Mexico, as well as some tiny lower-level spinups in the Caribbean, and a large mostly upper-level low in the central Atlantic. All neat features. Fortunately for those of us who can do without tropical cyclones in the area, surface pressures in all of these regions go the gamut from not low to rather high. Without surface pressures falling rather substantially from these levels, it will be difficult to nearly impossible to get a tropical cyclones birthing in these regions.
Perhaps the feature of most interest of these is this blowup along the coast of eastern Mexico, not only because it is closest to land, but also because there does appear to be a surface trof, however weak, under all of that mess.
To attempt a bit more of a rundown of these features:
Western GOM: Deep tropical moisture fanned by a ULL along the coast. A surface low, perhaps nothing much more than part of the monsoon trof and/or heat low, appears to be well-inland over old Mexico, and an additional surface trof may actually exist under the mess of disorganized showers and storms just offshore a bit. Buoy 42002 located at 25.17N 94.42W is now reporting generally light NNW winds, while Buoy 42055 located at 22.01 N 94.05 W, to 42002's south in the Bay of Campeche, is reporting generally SE winds of about 15-20 knots. At neither of these locations are surface pressures falling, and in fact are rising some and are now relatively high. Any development that might occur here will need several more puzzle pieces coming together just right, first.
In and around the Caribbean: Moderate to high shear abounds. Little mid-level spinups that develop from time to time wash out quickly, as anything closer to the surface gets efficiently mowed by the strong upper level winds and generally moderate to high wind shear in the area.
ULL at about 64W 30N: appears to have worked down to the mid-levels, a little bit, but any surface reflection that may be there is slim to none, and fleeting at best. Detrimental dry air encircles the ULL, and surface pressures in the area are very high. About a snowball's chance in southern Arizona during July of anything happening there.
| Storm Hunter |
| (Veteran Storm Chaser) |
| Wed Jul 18 2007 03:27 AM |
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Re: Waiting...But Not Quite There Yet
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well.. just a few of my thoughts.... i am particular interested in the tropical wave coming into the southern islands. Just to the SE... The ULL low in the Mid north carb i think is about to clear the area out for some waves to move along into.. there is already a tropical wave just over the middle nothern carb. (east of the ULL)... And with the surge of tropical feeds/mositure into southern TX and western GOM... I think we are about to see somewhat of a pattern change in the coming days/week... We are getting the troughs digging down out of the Upper midwest to the mid southeast then out to the east coast..... strong lows up in the hudson bay area of Canada.... this pattern looks somewhat similar to a few years back... I just don't see to many atlantic systems right now with the current setup... Pressures in the ATL are high, and don't look to change for some time.... think i saw someone post about a pattern like.... atl to the carb... and then up around into the GOM.. or into central america... almost keeping the atlantic side shut down... WATER TEMPS ARE WARM NOW... depth of warm water is increasing too in certain areas.
for the cape verde season.... i like to see how the dust levels are in a few months... a post for another day... (but the ITCZ is somewhat more active now in recent weeks!)
Just one note now... I would highly recommend to do final checks on you Hurricane Kits... I hear that gas prices may be goin up again soon... Use the extra money to supply your kits...
| cieldumort |
| (Moderator) |
| Wed Jul 18 2007 08:25 AM |
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Re: Waiting...But Not Quite There Yet
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New feature possibly worth watching, Storm Hunter points out there. That is one impressive wave. Additionally, I can't remember the last time I've seen the GOM & Caribbean get the dry out like is happening tonight (Link: Water Vapor Loop). I think it was at least a month ago, now. Also, a few pockets of low shear are also starting to pop up here or there in the region (Link), although the eastern Caribbean, where that impressive wave is about to enter, is running moderate to high at this time.
Will be interesting if this is a turning point in the region. Little by little, more and more of the indicators are turning positive per climatology, and with a recent MJO pulse now in effect over this area as well, these next few weeks could be intriguing.
| Beach |
| (Weather Guru) |
| Wed Jul 18 2007 03:16 PM |
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Re: Waiting...But Not Quite There Yet
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Our snowball out at 65W 30N:
http://www.ssd.noaa.gov/goes/east/tatl/loop-wv.html
Looks like it isn't ready to give up just yet. There seems to be circulation still at lower and middle levels.
It's still a 1000 miles away, so it has plenty of time to go poof...
or not.
| cieldumort |
| (Moderator) |
| Wed Jul 18 2007 10:45 PM |
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Re: Waiting...But Not Quite There Yet
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If the feature to the south of Brownsville, Tx. had its associated very weak surface low/trof centered a bit more offshore, it may have earned an Invest tag by now. As can be made out by zooming in (time sensitive) on this recent RGB-enhanced Visible (Loop), a bona fide lower level center of sorts has formed, but is just barely inland, now north of Tampico, Mx., and moving generally NNW, along the coast, but inland. For the better part of the last 48 hours deep convection has hugged this very weak center of lower pressure, and has pulsed higher and lower, but never really dissipated. Winds around Brownsville and much of extreme south Texas have now turned generally NE, offshore of there winds are E or ENE, and winds south of that convective vortice are generally out of the SE. Some of the low cloud features to its west in old Mexico generally moving in from the NW, W, and SW. Possibly a very weak closed circulation does exist at or very near the surface.
The ULL now centered south of Cuba is fast approaching and putting a squeeze on this feature, not only making the convection appear oblong while creating much higher shear over its eastern side, but helping nudge it along a little bit farther west, as it is also getting drawn inland by the retrograding inverted ULL over NE Mexico/E Texas. Conditions are simply not favorable for this one to pull it off. Maybe if something gives - by way of this, something currently unexpected - it has a chance to slide back offshore and/or reform offshore under less difficult conditions, but as of right now, I can make nothing out in the way of anything ready to do that "giving."
So, meanwhile, NE Mexico and extreme S Texas will be getting inundated with bands of squally heavy rain showers and thunderstorms embedded within larger expanses of lighter rain showers.
Other than that, not much out there I can see. Though I still take note that the waves rolling in from Africa have been longer-lived recently, and in general, the entire western Atlantic is not nearly as dry as it has been of late. Also, some models suggest a possible low forming off the Carolinas by a front pushing just offshore, but none that I have seen thus far indicate much if anything in the way of a warm core, there.
Edit: Surface low now very apparent in the Brownsville extended radar loop (possibly time-sensitive link). Indeed, a weak Tropical Low has formed - just barely inland -
|
danielw
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| (Moderator) |
| Thu Jul 19 2007 02:38 AM |
| Attachment |
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?Inland Low?
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That system/ trough has been getting a good bit of my attention.
Around 10am CDT this morning it had a perfect CDO look. Only the western 2/3 of the CDO was onshore.
Tonight the un-enhanced IR is showing some of the nicest striated bands that I've seen in the last few years. ( see my attachment above) Also of note is the quantity of lightning seen in the eastern ( offshore ) semicircle. In the attachment the lightning is the bright bluish-white specks in the RGB enhancement.
I'm also keeping an eye on the circular wave moving through the Lesser Antilles. More out of curiosity than climatology. Large arc type wave moving toward the NW, where most waves would be moving due West.
I'll have to look at the data in that area.
| Storm Hunter |
| (Veteran Storm Chaser) |
| Thu Jul 19 2007 03:55 AM |
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Re: ?Inland Low?
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hmm... very nice blow up of convection near 53w 10n... kinda coming in behind the wave in front of it, thats already into the caribbean... Noticed the CMC again trying to throw something up the east side of the US late this weekend/next week... For some reason, when CMC starts to jump around... i think its a sign things are beginning to change.. This wave/convection out in the ATL... got my attention as of right now... see if it can hold for another 24-48hrs as it approaches the islands... needs to gain some lat., and i think it will... like the wave in carb. is clearing the path somewhat for the next wave... i also noticed that in the atl, east of 40w and 10n or so... things are not that as hostile as say two - three weeks ago in the Upper levels... at the surface... still a good push though around the ridge in the Atlantic, from east to west....
[url=http://www.ssd.noaa.gov/goes/east/catl/loop-avn.html]Central Atlantic - AVN Color Infrared Loop[/url]
Water Vapor can kinda help show the mid-to-upper level patterns...near this feature
[url= http://www.ssd.noaa.gov/goes/east/catl/loop-wv.html]Central Atlantic - Water Vapor Loop[/url]
Just a sit and wait... see what happens... if it will make through the night or not.... waters get more warmer the more it heads west now.... and not to much shear aloft near it... didn't get much mention in the 8:05pm TWD tonight, except for [url=http://www.nhc.noaa.gov/text/refresh/MIATWDAT+shtml/182359.shtml?]Atlantic Tropical Weather Discussion[/url] ADDITIONAL SCATTERED MODERATE CONVECTION IS NOTED WITHIN 90 N OF THE ITCZ W OF 54W.
| Storm Hunter |
| (Veteran Storm Chaser) |
| Thu Jul 19 2007 04:35 AM |
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Water Temps
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Speaking of water temps... this is more of a Composite (Daily Sea Surface Temperatures) image... notice the warmth showing up... close to US and i noticed too... up of the New England to far NE... warming up quickly...
Real Time POES Imagery - Atlantic/East Pacific SST Loop
Looks to me that the GOM is cooking good now with warm water... depth of warm water is not that too bad neither in certain spots.
**Kinda see better signs too of La Nina down in the southern EPAC (near equator)
(mods can move this post, if need be)
| Storm Hunter |
| (Veteran Storm Chaser) |
| Thu Jul 19 2007 05:42 AM |
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Re: Water Temps
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Just looked at the 00Z GFS long range... and going back and looking at last few runs/days.... Long range, say late next week... toward end of the month, looks like we may see a pattern change take place... looks somewhat familiar too a few years ago (not as much as last year, but before that)... the trough of low pressure along the east US looks to turn more zonal in the northern US... and be replaced by a ridge of high pressure the eastern US into the atlantic... i think in the last couple of days, the long range GFS is showing some signs of a pattern shift, and how long it last, who knows... for a short time, or for weeks... only time will tell...
GFS
Almost looks like the pacific NW US... Northern Pacific towards Alaska is going to see a pattern change... the low area may get replaced with high pressure out off the coast? Would be great news for the SW US... where all the wildfires are. The change out west would affect the eastern US... almost looks like to set up a blocking pattern with the ridge off the east coast for tropical systems if they would form, around the end of the month...
Any others see this shaping up in long range??
| Doombot! |
| (Weather Guru) |
| Thu Jul 19 2007 06:18 AM |
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Holy cow! Can you smell what the CMC is cooking?!
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The CMC seems to go stronger and stronger each run. This is out at 108 hours from the 00 19th run. It's if this verifies, it's bad news for NYC.
(oversized image deleted - please use attachment or URL link.)
| allan |
| (Weather Master) |
| Thu Jul 19 2007 08:43 AM |
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Re: Holy cow! Can you smell what the CMC is cooking?!
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I hate to say this, but the CMC could be on to something with a storm hitting the NE.. but that strong? Maybe not. Why I think this could happen? Take a look at this loop of the wave at Lesser Antillis, notice the movement, it's NNW.. and the CMC picks this up around July 20, and turns this into a monster category 2-3 Hurricane Chantal hitting Montauk point, LI. It is something to watch, regarding that the CMC has done horrible this year, but it's record is not all that bad. It was correct with Alberto in 2006, and our 2 storms so far this year, it nailed Barry. Now look at the UKMET, it to has a storm forming a bit more north - westward and moves it up the coast, I still can't get the Cyclone Phase map for that model yet. The CMC has it fully tropical then hitting with some extra-tropical characteristics, but still a Hurricane landfall. Also notice on the second link, shear has decreased to favorable conditions in the path of this "possible" but not yet confirmed storm for the NE. So all in all, it could happen, but highly doubt it will be a monster in my opinion.
satellite (movement of the wave)
http://www.goes.noaa.gov/HURRLOOPS/huirloop.html
Shear map as of 00z
http://www.ssd.noaa.gov/PS/TROP/DATA/gparm/xyrshr.gif
| Hurricane29 |
| (Weather Guru) |
| Thu Jul 19 2007 01:30 PM |
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Re: Holy cow! Can you smell what the CMC is cooking?!
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I think the CMC is not to be taken serious as its done very poor on genesis so far this season.Also i in opinion the CMC model is not to far behind from the NAM when it comes to forcasting tropical cyclones.
On another note strong wave pushing into the islands....Some mid-level rotation there.
| Robert |
| (Weather Analyst) |
| Thu Jul 19 2007 03:15 PM |
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Re: Holy cow! Can you smell what the CMC is cooking?!
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This A piece of Joe bastardie's weather out look for this morning
Oh, by the way, a home brew watch may be issued for off the southern Atlantic coast, as the tropical wave over the eastern Caribbean comes northwest and entrains itself into a frontal boundary that will be off the south Atlantic coast. The trough split that occurs may leave this area as one where in-close development can take place and I think the Euro and to some extent the UKMET is on to this. Finally the euro is seeing what is going to happen as it is weaker with the split rather than trying to leave a close-off low over the Appalachian
| allan |
| (Weather Master) |
| Thu Jul 19 2007 03:17 PM |
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Re: Holy cow! Can you smell what the CMC is cooking?!
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Yes it is a poor model but that pic of the wave in the carribean you posted is the wave that the CMC has developing.. look at where it's moving, not west. It's just something to watch..
The CMC takes this wave over the islands and rapidly turns it into a Long Island Express like storm, because of teh possible steering currents last year, people would have been watching this more. I will continue to moniter it, it may be a bad forecast model, but it IS a forecast model and should be at least monitered on that weird but possible situation. The wave btw is moving in a NW direction and is firing up convection due to currently marginal to low shear (10-15 knots). This one has a chance.
1:00 p.m. - New CMC run is more reasonable, it has a weak TS hitting the NE instead of a Hurricane. What also makes me believe more that the CMC could be true is that a small circulation has formed on the north part of the wave, and ENE of Puerto Rico. I believe the CMC is hinting that this area of interest is the one to be the player for the NE. It's very clear, convection is good, maybe 97L will come around later tonight if convection and the circulation persists.
| Ed in Va |
| (Weather Master) |
| Thu Jul 19 2007 05:29 PM |
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Re: Holy cow! Can you smell what the CMC is cooking?!
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CMC has now backed off to a much weaker system:
http://moe.met.fsu.edu/cgi-bin/cmctc2.cg...;hour=Animation
| Tropics Guy |
| (Storm Tracker) |
| Thu Jul 19 2007 06:16 PM |
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Re: Invest Soon?
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Looks like the area of weather in the NE Carib sea is trying to organize ever so slowly., hard to tell where a LLC may be trying to form at this time. May see an invest on this soon!
http://www.ssd.noaa.gov/goes/east/tatl/loop-vis.html
| ElizabethH |
| (Meteorologist) |
| Thu Jul 19 2007 07:13 PM |
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Re: Invest Soon?
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The CMC has been all over the place so far this season. BUT finally it looks like it may be onto something. The 12z run today has something coming into NE 108-120 hours out. The gfs and the UK put something (not as aggressive) in there around the same time.
As we enter late July and into the peak of the season, I'm sure there will be several discussions about tropical waves starting with "did you see the CMC this morning?" As of right now, I'm not ready to completely right this Canadian forecast off. I am sure we will all be keeping an eye on things. Just like the mess over the Lesser Antillies...shear is low in the Caribbean and dry air in the mid levels is eroding just a bit. I'm a little nervous about anything moving into those warm warms at this time.
| Ed in Va |
| (Weather Master) |
| Thu Jul 19 2007 07:55 PM |
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Re: Invest Soon?
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From the afternoon Albany (NYC) NWS discussion:
A SURFACE LOW FORMS NEAR CAPE HATTERAS FRIDAY EVENING AND
MOVES NORTH TO OFF THE DELMARVA COAST BY NOON SATURDAY. AT
THIS TIME IT APPEARS ITS EFFECT WILL BE LIMITED TO SPREADING
| Storm Hunter |
| (Veteran Storm Chaser) |
| Thu Jul 19 2007 09:11 PM |
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Re: Invest Soon?
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hmm... there is more model support today with this feature off the east coast in the coming days... CMC has been all over the place in the last 3-5 days... heck, had a strong TS/Hurr. in the GOM three days ago... ranging from south Florida to way over in Texas...... now with this wave in the Carb. it began taking it straight up the east coast......Hard to think it was going to happen, pressures were just to high off the east coast... and it was the only model showing something... now with the next trough digging down....we might see some trying to form... as far as being tropical... i not quite sure yet.... I think this may be more of a trough merging with the tropical wave and may throw up something along the NE... (more of a frontal low?)
I am now seeing better agreements coming into long range models about a shift in the wx pattern in the long term runs... upper pattern looks more favaroble going into late July into Aug.,... The ridge appears to work its way into the east US... Shear in the atlantic looks to be more favorable too...
For those who like to see the fronts/sea pressures Loop of sea-level pressures and fronts from the HPC... Just gives an idea of the pattern... NOT OFFICIAL forecast...