MikeC
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| (Admin) |
| Tue Aug 28 2007 10:19 PM |
Tropics Acting Up Again
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Like usual with late August, you can't leave the tropics alone for a week without something happening. After a few quiet days we have a few things to watch, nothing terribly imminent, however.
#1 is a disturbance East of the Yucatan, which is too close to land to do much, but may have to be watched later Movement is to the west, however, any northward component from due west would bring the center over water - it'll be close. Significant rainfall likely for Honduras, Guatemala, Belize and the Yucatan.
#2 is being tracked as 94L, and may form into a depression over the next few days. This is something to watch as it may affect the Caribbean. Currently it is heading west and the early model predict runs show it going into the eastern and southern Caribbean. But as usual, wait for trends to develop to get a real foothold on it. Currently the models aren't really keen on developing it. If this system persists, however we may have something. Odds are at the moment that it won't amount to much.
#3 is a disturbance Southeast of Wilmington, NC, which is worth watching if the storm persists over the next few days. We need to watch this as the ocean temperatures in the area are plenty warm enough to support a storm. Right now shear and other conditions are keeping it in check.
More to come on all of the above soon.
{{StormLinks|94L|94|6|2007|1|94L (East Atlantic Wave))}}
{{StormLinks|95L|95|7|2007|2|95L (Disturbance Southeast of Carolinas))}}
{{StormLinks|96L|96|8|2007|3|96L (Another Disturbance Southeast of Carolinas))}}
{{StormLinks|97L|97|9|2007|4|97L (Disturbance in Bay of Campeche))}}
| Unregistered User |
| (Unregistered) |
| Wed Aug 29 2007 12:27 AM |
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Re: Tropics Acting Up Again
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94L is weak as thunderstorms are firing up to the southwest of the low pressure. This may be the start of development but I will be more sure if this expands overnight. There seems to be a weak outflow developing. Its entering a better area for development and rate this as a 4 tonight. There are too many ifs at this point to be sure but slow development is possible. Long range it looks like a carribean storm. Thats as far as I will go until a more consistant sign developes with this system. More tommorow I believe.
| cieldumort |
| (Moderator) |
| Wed Aug 29 2007 12:31 AM |
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Re: Tropics Acting Up Again
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The tropical wave/mid-level low combo approaching the Yucatan has now been added as an Invest (Link to close-up IR). Despite repeated proclamations to the contrary, it is getting to be very hard to argue against a northward component to its movement and development, and even the 8PM TWD now explicitly describes it as being over water "A STRONG TROPICAL WAVE IS OVER THE WESTERN CARIBBEAN ALONG 85W S OF 22N. "
Upper-level winds over the last several hours have become increasingly favorable, with high pressure forming aloft, inducing some outflow in just about all quadrants.
The low pressure which exists just above the surface to the SE of North Carolina has plenty of time to develop while over the toasty gulf stream and nearby waters. Upper-level winds are only marginal, but are expected to become at least somewhat more favorable over the next day or so. Probably a fish spinner if it transitions, but that's no guarantee.
Really, these two are already very close to land, and bear close watching. 94L is at least 48 hours before affecting the Antilles.
| dem05 |
| (User) |
| Wed Aug 29 2007 12:42 AM |
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Re: Tropics Acting Up Again
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EDIT: While I was prepping the post, Cieldmort was already posting some of this info...Sorry for the duplication!!! Looks like we are sharing some of the same ideas!
)Well...the Western Carrib. disturbance is now an unassigned Invest. That is, no invest number yet, but a floater invest has been placed on it.
Overall, the picture with this invest is different that what happened during Dean. Besides Dean being a hurricane, there are several differences at the mid and upper levels. Wouldn't rule out development just yet, and I wouldn't rule out Cieldmort's thoughts in the previous thread. However, I am not ready tocall for development or movement of this disturbed area...I'd rather outline some things to watch:
- First, on the last visible images, there is no evidence of a surface circulation. Please note the clouds moving off to the west over the Yucatan.
- Second, thunderstorm consolidation...With the tradewinds seeming tomove through at a decent clip from east to west, I'd suspect that any developments would have to originate at the mid levels...and be transferred to the surface. There is good thunderstorm clustering tonight...We will have to see if this "blob" is "go weapons hot for a diurnal thunderstorm maximum". If so...and if the thunderstorms last through the day...and mid level vorticity at the 500mb level or so exists... it will have a shot at slowly working toward the surface.
-Third, The upper level low as seen on the Western Atlantic and Gulf of Mexico Loops...
Western Atlantic Loop: http://www.ssd.noaa.gov/goes/east/watl/loop-wv.html
GoMex Loop: http://www.ssd.noaa.gov/goes/east/gmex/loop-wv.html
If you watch these loops, I believe you will see the ULL over the Yucatan is dissapating...but it is being replaced by a new ULL over the East-Central Gomex. Interesting...It is propogating westward slowly, but unlike Dean, It isdue north of this disturbance...Justsomething else to watch...Mean time, Upper Level conditions could become more favorable. Also, the ULL may influence a more NWerly heading,
- Fourth...Models did not handle this evolution well...They do not see a new ULL low forming in the Gulf as I can see. Also, at this point, most 12Z models showed the main vorticity over Nicaragua/Hondoras...As you can see, this is not so.
- Fifth and finally...a wild card against development is another unassigned invest that is taking shape and was assigned a floater at the same time...It is south of Guatemala on the Pacific Side. If it develops...it is in close enough real estate to say that the disturbance in the western carribean will not develop...So this is something to watch too...It actually looks like it has better odds and that would put an end toany concerns in the Gulf or Western Carribean Link: http://www.ssd.noaa.gov/goes/flt/t3/loop-vis.html
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Ed Dunham
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| (Former Meteorologist & CFHC Forum Moderator (Ed Passed Away on May 14, 2017)) |
| Wed Aug 29 2007 01:36 AM |
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Re: Tropics Acting Up Again
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Note that there was a low pressure center associated with this wave, but it has become increasingly difficult to locate it. At 00Z it seemed to be right on the coastline of east-central Honduras - due south of Roatan Island. Over the last couple of hours the wind at Roatan has been out of the east at a steady 25mph.
I'm sure that the thinking at NHC was that if this center remained over land, the system would not intensify. To put the TWD in proper context, here is the complete paragraph:
"A STRONG TROPICAL WAVE IS OVER THE WESTERN CARIBBEAN ALONG 85W S
OF 22N. DISORGANIZED SHOWERS AND THUNDERSTORMS EXTENDING FROM
HONDURAS NORTHEASTWARD TO THE CAYMAN ISLANDS ARE ASSOCIATED WITH
THIS TROPICAL WAVE. DEVELOPMENT OF THIS SYSTEM IS NOT EXPECTED
DUE TO PROXIMITY TO LAND. HOWEVER...LOCALLY HEAVY RAINFALL IS
POSSIBLE OVER PORTIONS OF CENTRAL AMERICA AND THE YUCATAN
PENINSULA DURING THE NEXT DAY OR SO AS THIS SYSTEM CONTINUES
WESTWARD AT 10 TO 15 KT. THE WAVE IS ALSO HELPING TO INDUCE
SCATTERED SHOWERS AND TSTMS OVER WESTERN CUBA."
Cheers,
ED
| HanKFranK |
| (User) |
| Wed Aug 29 2007 02:18 AM |
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ready
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o-k. three things looking good tonight.
they're all well outlined so far... i'll just toss some ideas and see what happens.
94L--that's a storm. it's not developing quickly or anything, but it will be. don't buy much into the guidance as there will likely be more storm there than indicated... but based on its location contact with the caribbean is highly possible. upstream developments will determine it's future track. it's going to have to fight with dry air, but should win out after a bit.
western caribbean--doesn't want to follow the rules. i thought the nhc take of land interaction was sure fire, but the models taking it on a near shore trajectory turned out to be on the ball. possible that high level shear is helping whatever mid-level vorticity is there to translate north, and seems to be providing more ventilation than damage. belize is in the way, though. if it keeps its track more wnw it will cross more ocean in the BoC and possibly succeed where the low that invaded mexico yesterday failed--whatever is at the surface will travel over land and likely allow the upper circulation to become better defined... and take right off when it goes over water.
off the carolinas--didn't see that coming. more shortwave energy got left behind than projected by most models, on a more southerly trajectory. it's going to be stuck in a col and probably move erratically late this week. a shortwave should clip by around weekend time, but it's unclear if this will shunt it off. could just nudge it west then let the ridge grab it again. thing i'm not seeing is how it will shape the environment. this sucker looks like it will develop. it is going to modify the nearby upper features, and lay the groundwork for whatever 94L is to do it's thing.
all three systems can develop. the wave coming off also has some potential. ought to be something out there tomorrow, and probably at least two somethings on thursday.
HF 0218z29august
| Storm Hunter |
| (Veteran Storm Chaser) |
| Wed Aug 29 2007 02:34 AM |
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Re: ready
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Well.. this thread is got some good posts in it tonight... out of the three area's we are watching... i think two of them have a good chance of forming into a tropical low. 1st. the area of the S. Carolina coast... its going to be around for a few days... while sitting over the gulf stream, its going to become better organized in my opinion... i do think that the next front coming into the east coast this weekend however will catch it and drag it off to the NE. I would expect to see surf pick up along the SE coast in coming days, and some good NE flow down the east coast, perhaps some dry air? #2. 94L in the atlantic... if it can survive another two-three days in the atlantic... then its going to be some player down the road in the carb.!!! #3 has impressed me tonight, the latest TWO doesn't give it much chance, but the mid and upper level look impressive...(i would think that the Navy would throw up an Invest tag on it tonight around mid-night)... Pressures in the western Carb. are not falling at the surface at last check.. there is really a strong east to west flow at the surface. If it can mix down to the surface, it may have a chance...i'm just not sure it can right now... If the storms presist for the night, it may need some watching...Man, i feel bad for the folks that just went threw Dean, MORE TROPICAL mositure on the way.
| Hugh |
| (Senior Storm Chaser) |
| Wed Aug 29 2007 02:36 AM |
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Re: ready
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Well, I'll throw my 3 cents into the pot, for what it's worth, which is probably something on the order of a penny...
I'll start with the Caribbean since it's the closest to land. I can't detect any circulation on the floater... BUT the convection is pretty impresive. It appears to me that the main offshore convection is moving almost due NORTH, though, not WNW. If it can somehow find a nice warm body of water away from the land that its near, it's got a good chance. I'm thinking the Bay of Campeche, or the east or central Gulf, depending upon where the convection goes. It should be designated 95L before too much longer if it holds together, IMHO anyway.
94L is not looking impressive. Lots of water ahead of it, so it's got a chance down the road.
| Clark |
| (Meteorologist) |
| Wed Aug 29 2007 02:49 AM |
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Re: ready
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A few comments, largely restating a lot of what HF had to say with a bunch of different words (hey, it was good stuff, and I can go with that!)...
94L: it may well be a storm, but it's embedded in one of the strongest SAL outbreaks of late right now. Low-latitude runner for now; let's see what happens once it gets to the Caribbean and the dust has had a chance to settle and/or mix out.
Carib disturbance: kinda reminds me of some of those pesky disturbances of 2005 that ended up spawning Bret, Gert, and Jose (among others). If it follows a similar trajectory, it's not out of the realm that it does something similar to that.
Carolinas disturbance: starting to get to that time of year where frontal boundaries make it far enough south to get interesting when they stall out over the Gulf Stream. It's already got a better-defined feature about which convection can develop and a system can be born as compared to the last case we had of this (northeast Gulf). Plugging my own WRF model for a second, it did suggest this morning that this will linger around for the next three days and slowly develop. Like the Caribbean disturbance, not out of the realm of possibility.
Wave train: two features of note, one due south of the Cape Verdes and another due east of them along the coast of Africa. SSTs are still below normal out there but at or above typical thresholds; it's the vertical instability associated with the strong ridge out there that is now the main problem. The models (GFS and ECMWF) are starting to get that 'look' to them, developing multiple features out that way over the next two weeks. Climo would argue for that alone, but so would the overriding atmospheric conditions.
The wave coming off the coast is probably too far north, though it does have a nice reflection about 12N/10W; the one south of the Cape Verdes will probably follow a similar path to 94L albeit without as much dust to contend with. Wouldn't be surprised to see one of these two eventually develop, with attention then turning to another wave about 14N/10E late in the week.
All of the atmospheric features that we'd normally want to see for a sustained active period in the tropics -- particularly in the deep tropics -- are starting to come together. I agree with HF's comment of "something" being out there tomorrow and possibly two "somethings" by Thursday and will go a step further to suggest a third "something" by Labor Day. Whether these somethings are more like the most recent 99L and don't really get going or if they end up being classified tropical systems, well... I'll leave that guessing game to everyone else.
| doug |
| (Weather Analyst) |
| Wed Aug 29 2007 01:58 PM |
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Re: ready
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95L is posted for the low off the Carolinas drifting South along 75W.
| Ed in Va |
| (Weather Master) |
| Wed Aug 29 2007 02:20 PM |
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Re: ready
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Early guidance for 95L (click on early guidance):
http://euler.atmos.colostate.edu/~vigh/guidance/
| Storm Hunter |
| (Veteran Storm Chaser) |
| Wed Aug 29 2007 03:26 PM |
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Re: ready
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hmm... i think we can add a fourth area to the discussion soon... the area to the SW of the Cape Verde Islands looks impressive this far out! (we may be able to drop the tropical wave that ran into central america...)
Met-9 Airmass 24img loop... **Need fast connection**
| hurricane80 |
| (Registered User) |
| Wed Aug 29 2007 05:26 PM |
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Re: Tropics Acting Up Again
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I just checked the FSU ensemble (00UTC) and it shows Invest 95L moving SW towards Central Florida in 72 hours. Does anyone also see this?
| Wingman51 |
| (Weather Guru) |
| Wed Aug 29 2007 05:50 PM |
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Re: Tropics Acting Up Again
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I haven't seen these models on the board before. Do they measure something that the others do not? Can we get some feedback from some of the more knowledgeable sources here about these new models. Thanks
| Unregistered User |
| (Unregistered) |
| Wed Aug 29 2007 06:00 PM |
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Re: Tropics Acting Up Again
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Clark should probably answer this and if i am wrong i hope he changes my post
but the way i understnand it is the fsumm5 model is being initialized with different model info
and these are the outputs...
reliable? i would say so as much as any of the better models
| Clark |
| (Meteorologist) |
| Wed Aug 29 2007 06:16 PM |
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Re: Tropics Acting Up Again
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Regarding the FSU models...
We're running two versions of the MM5 during the tropical season, one that uses the GFS for initial and boundary conditions and one that uses a combined GFS + GFDL dataset for initial conditions. The latter gives a better initial representation of any features in the domain, like 95L and TD Ten-E in the East Pacific.
The MM5 is a mesoscale model primarily designed for research purposes. The Air Force used to run an MM5 in real-time for the tropics with results that weren't anything to write home about. I would put more stock in the recognized global and mesoscale models such as the GFS, GFDL, and ECMWF than on anything our MM5s spit out.
That said -- this feature off of the Carolinas (95L) is probably our best candidate for our next tropical cyclone in the basin. It'll take a day or so to undergo warm core transition (or tropical transition), but by late tomorrow I expect we'll likely have something of interest. It will likely meander around in the Gulf Stream for the next few days and with weak steering currents, erratic motion can be expected. Interests from the central Florida coast northward need to watch -- but not worry -- about this one over the coming days.
| ElizabethH |
| (Meteorologist) |
| Wed Aug 29 2007 07:14 PM |
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Re: Tropics Acting Up Again
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Well, the models aren't that excited about the THREE disturbances out there. In reality, we only need to "keep an eye on" the one off the East Coast and the one out in the Atlantic. It's faily unique to see absolutely nothing as far as development in with the models this time of year. Conditions will slowly become more favorable for development with the Atlantic tropical wave, but we'll have a little time to watch it become a Depression.
Clark's right, I think 95L will become a despression first.
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Ed Dunham
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| (Former Meteorologist & CFHC Forum Moderator (Ed Passed Away on May 14, 2017)) |
| Wed Aug 29 2007 08:35 PM |
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Re: Tropics Acting Up Again
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When things are quiet at a time in the season when things are not supposed to be quiet, I guess that storm trackers tend to get a little antsy. I tend to agree with your assessment - waves and Invests aside, there isn't anything in the basin that shows even a hint of better organization. 95L has been blasted by shear and reduced to a barely recognizable low-level swirl. 94L is also under a sheared environment and remains poorly organized - it could eventually amount to something, but its going to take more than a couple of days. Even the latest wave off of Africa looks anemic. The elements that define the overall 'pattern' in the basin still have not changed, so I really don't see much of anything developing for awhile.
Now that I've said all of that, I'm sure that something will pop up tomorrow (but I doubt it)
Cheers,
ED
| Ed in Va |
| (Weather Master) |
| Wed Aug 29 2007 08:54 PM |
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Re: Tropics Acting Up Again
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Agreed. What looks healthiest, at least in terms of convection, is the area over the Yucatan. If that holds together until it gets over the BofC, there could be some quick development. Could be an issue for TX down the road.
| Storm Hunter |
| (Veteran Storm Chaser) |
| Wed Aug 29 2007 09:03 PM |
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Re: Tropics Acting Up Again
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well... Looks like we have three lows on the map in the tropical atlantic... How many will form? Good question
... just throwing in my two cents... just got back into town (PC) and took a look at the sats... I am much more impressed with 94L today, even though its doesn't have that deep convection going....Seems to me there is more cyclonic turning at the surface, (may be more enlongated) then there has been in the last few days... but watching the Vis floater ....kinda can see where the dust/dry air could be...to the north of the tropical wave.... I would think a center/low is around 46-47w 11-12n ish....(I know its marked as a 1010mb low)... it's moving to the west at about 10-15kts.TWD, 2:05pm edt
as for 95L... its clearly exposed this afternoon... nice little surface reflections is easy trackable... Above (Mid-Upper level...just seems to Dry above 95L right now for anything to happen in the short term. If it can hang on as it appears to be drifting to the south, if should reach the warmer gulf stream and give its self a chance...
Well the latest tropical run suite TROPICAL CYCLONE GUIDANCE MESSAGE from about 18:00utc... keeps both atlantic systems in play...
Recon plan from this morning:
TCPOD NUMBER.....07-097
| nc_tropical_wx79 |
| (Weather Guru) |
| Wed Aug 29 2007 09:23 PM |
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Re: Tropics Acting Up Again
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I know this doesn't have anything to do with the center being exposed but w/ 95L lost/decrease in convection have to do with it making the transition from low attached to a front to a tropical low? Lows that transition from cold to warm core as they do change do they loose convection and refire it again once they become warm core and feed off of the ocean water? (sorry hope my question is understandable and not wordy or confusing).
| Clark |
| (Meteorologist) |
| Wed Aug 29 2007 09:51 PM |
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Re: Tropics Acting Up Again
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Quote:
I know this doesn't have anything to do with the center being exposed but w/ 95L lost/decrease in convection have to do with it making the transition from low attached to a front to a tropical low? Lows that transition from cold to warm core as they do change do they loose convection and refire it again once they become warm core and feed off of the ocean water? (sorry hope my question is understandable and not wordy or confusing).
Nah, and in fact it is usually the persistence of convection that signifies a system undergoing transition to a warm-core entity; it suggests that the ingredients are in place for a tropical system to survive and helps build the mechanisms by which oceanic warmth can be carried to the upper levels.
Sometimes you'll see tropical disturbances in the deep tropics build convection, have it die out, and then build it again and develop -- but it's somewhat different than what we're looking at here (even though it does help erode the very weak cold core believed to be associated with tropical waves) as it relates more to the development of a vortex than the transition of a pre-existing vortex.
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danielw
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| (Moderator) |
| Wed Aug 29 2007 09:54 PM |
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Re: Tropics Acting Up Again
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Here's is a near perfect sat shot of what WX79 is mentioning above... I think.
http://www.ssd.noaa.gov/goes/flt/t2/img/2007241_2045vis.jpg
Almost appears to have a sheared mid to upper level circulation.
Surface circ. is near 30N/ 76W and mid level circ center appears to be near 30N/ 73W or about 150 miles to the east of the surface center.
http://www.ssd.noaa.gov/goes/flt/t2/vis-l.jpg
http://www.ssd.noaa.gov/goes/flt/t2/jsl-l.jpg
The red area on the JSL enhancement is normally associated with deeper convection.. and I've found that the 'red' indicates the most likely area for lightning in tropical systems.
| madmumbler |
| (Storm Tracker) |
| Thu Aug 30 2007 11:54 AM |
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Re: Tropics Acting Up Again
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I wake up and there's FOUR invests on the NRL site????
It looks like 95L and 96L are both the Atlantic system off of SC, or are those two separate systems they're focusing on??
Can one of the mets please explain this?
| Hugh |
| (Senior Storm Chaser) |
| Thu Aug 30 2007 12:06 PM |
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Re: Tropics Acting Up Again
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Quote:
I wake up and there's FOUR invests on the NRL site????
It looks like 95L and 96L are both the Atlantic system off of SC, or are those two separate systems they're focusing on??
Can one of the mets please explain this?
I'm not a met but I heard the explanation on CNN
The system off of the southeast Atlantic coast actually *is* two distinct low pressure areas, and thus, two invests would be warranted. They won't BOTH develop (knock on wood), and I would *think* the fact that a second low has developed (the northernmost low developed overnight, according to the NHC's TWO), that would indicate that the first low is less likely to develop.
Bay of Campeche system is too close to land, and the Atlantic fish-swimming system is not looking very impressive this morning, to me.
| doug |
| (Weather Analyst) |
| Thu Aug 30 2007 01:02 PM |
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Re: Tropics Acting Up Again
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A quick and brief look this morning: it looks as if 94L is organizing a bit more, as predicted. My guess is this is an important day for this system as it seems to be less influenced by the SAL and is developing a low latitude feeder system for energy..Of the current systems of interest my guess is this one will be classified first.
I don't have a real good feel for the two headed system(s) in the ATL which are transitioning a bit. They may devlop seperately, if I can differ from the previous post...I think the northern most of the two is moving out NE but the second is still drifting south and the distances will only slowly increase. I don't see the northern one being purely tropical, but the second one if it goes would more likely be a warm core, IMHO.
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danielw
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| (Moderator) |
| Thu Aug 30 2007 01:28 PM |
| Attachment |
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Re: Tropics Acting Up Again
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Looks like you all have the morning wrap on the three systems.
94L is looking much better to me than 12 hours ago. Especially with the beginnings of the high thin cirrus outflow fingers on the western semicircle. 94L still lacking/ slacking in the eastern semicircle.
http://www.ssd.noaa.gov/goes/flt/t1/img/2007242_1245vis.jpg
95L appears to have consolidated over the lower level circulation that was visible late yesterday. However the convection is on the low side. (Sat shot is just north of the present center...as it appears that SSD has not moved the shot to follow the storm)
http://www.ssd.noaa.gov/goes/flt/t4/img/2007242_1245vis.jpg
96L-the most northern system. Has the better satellite signature of the three systems. Moderate or higher convection colocated near the center of circulation. Both a poleward and equatorward outflow channel... if you will. Actually had a decent signature late yesterday. Better than 95L off of Florida.
http://www.ssd.noaa.gov/goes/flt/t2/img/2007242_1215vis.jpg
97L System in BOC. Looks like the area that Dean clobbered a few weeks ago is going to get some more rainfall. That's my take on the 3 or 4, depending on what you are counting, systems.
http://www.ssd.noaa.gov/goes/flt/t3/img/2007242_1245vis.jpg
The numbers here may differ frfom the NHC or NRLMY sites. As I'm using the SSD satellite page for numbering.
See attachment for latest visible of 95L and 96L.
| Storm Hunter |
| (Veteran Storm Chaser) |
| Thu Aug 30 2007 03:21 PM |
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Re: Tropics Acting Up Again
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well, someone threw the switch on!!!
Out of our invest list right now, 96L looks to be the most impressive one. It has a small window to be become a TD, before the front grabs it and takes it off to the NE. The low to the south of it... 95L can be seen on vis sats.... drifting to the SW... as for 97L... well you can tell the BOC still has warm waters... but running out of time. 94L... i think it getting caught up more into the westerlies now... so its going to be interesting... warm waters ahead.**Notice TAFB (Surface Map) and NHC are putting more stock into 94L now.. TCPOD-07-098 puts a few flights out there.**
| cieldumort |
| (Moderator) |
| Thu Aug 30 2007 03:45 PM |
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Re: Tropics Acting Up Again
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96L to the ne of 95L (talking about the two Gulf Stream lows for those wanting reference) has, imho, had the upper-hand for the better part of the last 24 hours, of the two, and I was admittedly surprised that there was not a separate invest tag on it - so kudos, I suppose. Clearly, its presence so close to 95L has been hampering 95s development. This is probably a situation not terribly unlike the unnamed tropical storm of 2006 and Beryl, with the exception that 95L continues to drift S-SE, and has been weakening.
For all practical purposes 96L is almost there, already. Recent scatterometer images strongly suggest that the surface low is now just about nuzzled back under its deeper convection. 95L is probably not going to be too far behind, but only provided it can begin taking up the favorable conditions 96L has somewhat robbed from it, so far.
94L clearly is freeing itself from the tight grips of all of that SAL which has been inhibiting development, and now has a fairly well-defined convective coc. Probably not fully back down to the surface, as it degenerated into an open wave at the surface yesterday, after having had a surface low prior days.
97L in the BOC is running out of time (ocean) unless it can begin taking a more northwesterly course, again, but this seems to have ended in much the same way (interestingly) that it did so for Dean ... generally WNW and then about due west until landfall. Unless it slows down a great deal, stalls, or begins moving NW, the best it can probably achieve is minimal TS, and that might be generous. Regardless, it is guaranteed to be a prolific rain-maker... and apparently over more yet more areas that simply do not need any more prolific rains.
In summation, given current trends, I wouldn't be surprised to see a TCFA issued today for 94L & 96L, and to lesser chances 97L & 95L. As for bugging mainland U.S., I think we should be watching 94L & 95L the most. 96 will likely continue on its merry way out to sea, and 97 is hugging old Mexico.
| doug |
| (Weather Analyst) |
| Thu Aug 30 2007 03:55 PM |
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Re: Tropics Acting Up Again
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I agree with the last post...96L has the best signature now. 94L is coming along but is still hampered by its environment...if it were more centrally located in the envelope of moisture that is behind it ,it would be a storm by now...it is trying to grab that and hence some convection SE of the llc is growing.
the other two: 95 L is at best a sharp inverted V wave that is now being pushed east by the ridge exiting the SE coast . I don't see a closed low there and the western component is at the base of the trough to its west. In fact this is caught in that trough...I don' see this being a player.
97 is out of time as stated.
| scottsvb |
| (Weather Master) |
| Thu Aug 30 2007 04:02 PM |
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Re: Tropics Acting Up Again
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Well looking at data and sat obs 94L has the best chance of any. It does have a LLC and winds are 25-30kt with higher gusts.. the shower activity is also close to the center. Dry air is inhibiting more development but if T-Storm activity picks up tonight...recon will go in tomorrow and find a Tropical Storm.. but lets see what tonight brings first. 50%
96L just doesnt have the mid-circulation and LLC together..plus its running into a front....I think it will be a Baroclincal low as the midlevel takes over and strengthens while the LLC merges with the front. So no development here. 20%
97L doesnt have a closed circulation and is running into MX before any development will take place 20%
95L weakening elongated trough and a weak llc... 10%
Pretty much high pressures and dry air continues this year. Probably be around labor day before we get a good storm to come off Africa....94L has the only near term shot.
| doug |
| (Weather Analyst) |
| Thu Aug 30 2007 08:00 PM |
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Re: Tropics Acting Up Again
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95L is no longer a feature of interest apparently...somebody must be reading all the posts here, I guess?
94L is fighting to get organized...I see some persistent convection in four distinct locations east and Se of the LLC, and some now on the WSW section. BUT there is evidence of shear across the system as seen by blowoff SW -NE, and some low level type outflow boundaries consistent with interaction with dry air,,,continued development will be a struggle.
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danielw
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| Thu Aug 30 2007 10:41 PM |
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Re: Tropics Acting Up Again
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Amazing consensus with the last few posts.
There is normally a slight difference of opinion among posters. But I can't recall seeing this many post in agreement. For the most part.
Must be the storm heading and distance away from Conus!
94L has a long way to go. It has consolidated most of the convection near the center. But the outer periphery is still irregular. (using rgb and jsl only)
| Unregistered User |
| (Unregistered) |
| Thu Aug 30 2007 10:42 PM |
Re: Tropics Acting Up Again
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94L is becomming better organized this evening as satellite images showing an increase in thunderstorms to the south and east of what looks like a center of low pressure. Upper level winds have dropped to 5-10 knots and actually look to lighten further over the next 48 hours. Water temperatures are at 83-85 degrees and temp. should incease as it gets into the carribean. There is still dry air to its north though this should only hold development down over the next 24 hours as water vapor is showing a slight increase in moisture over the system. 48 hours ago I felt it was a 4 now have increased to a 5-6 range. I would like to see tommorow mournings satellite before I increase higher. Models are still mixed as development goes but the track seems to be a west to w-nw for the next 72 hours. I feel the models hold a ridge to its north a bit to strong as an old frontal boundary and a new front moves off the east coast this weekend. I'm looking for a more w-nw as it enters the carribean and a nw early next week before the ridge rebuilds due to a trough over the middle of the US. Turning it back to w-nw or west in time. So yes I feel if this system developes its a western carribean and gulf storm. Too early to even go this far but its a calculated guess. Just a note if anything does develope off the coast of Florida to NC then this may change the track of 94L. Something to watch as I believe next week will see a increase in activity across the atlantic so the quiet before the storm as they say.
| allan |
| (Weather Master) |
| Thu Aug 30 2007 11:20 PM |
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Re: Tropics Acting Up Again
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94L is one interesting system.. I'm not in too much dissagreement on the track but looking at the troughing situation, this should likely move more into the GOM in my opinion. Although.. what i'm wondering is why models are having such a hard time on the strength? 94L should be a TD easily either late tonight or in the morning as it continues to do it's thing tonight.
On to our next area, poses little threat but should stay away from the USA. 96L, very subtropical looking to me, I got to dissagree with the "baronic low" that one person was mentioning, however, it still may not be named, we'll see what happens with it tonight, if it doesn't get classified now, it could be classified at post analysis with our last 96L lol. The track is simple, not a fish, but a canadian storm.. wouldn't be surprised if it affected Maine.
97L may run out of time to develop in my opinion, should be in Mexico sometime at noon tommorrow as either an invest or maybe just MAYBE a TD.
(dubbed) 95L by NHC, can't say no or yes on development, the UKMET still shows a stalling low near the Florida coastline, but as a friend of mine told me earlier, I give it less than a zero chance.
Overall, it's a really good that we will be tracking a classified system!
| HanKFranK |
| (User) |
| Fri Aug 31 2007 01:15 AM |
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surprise surprise
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the can't-quite-develop theme continues.. with the yucatan system almost making it, but hugging the coastline, the stuff off the east coast remaining sheared, and good ol' 94L trucking along half made and without a care. overall it's been an unusually quiet august for a la nina year. yeah, i'm sure dean with it's powerhouse run added a ton of NTC activity, but aside from that august has only managed a weak trickle. the atlantic is overall running a good bit warmer than normal... strange that atmospheric conditions haven't allowed more action to take place. we're getting tight on the statistical peak of the season, so the puttering tropical cyclone activity is not likely to continue.
disturbed weather should hang near the east coast/southeastern u.s. and keep trying to spawn a system. it hasn't succeeded yet, but with the sort of blocky, persistent weakness hanging off the eastern seaboard it becomes a likelihood over time. 94L has real potential to cause trouble if it can develop, but most of the models continue to show a lack of support, and if it does develop it will be tracking more or less along dean's wake. the monster ridge that pushed dean hard west isn't in place, so even though the models show a weak storm tracking westward, a stronger storm could still be a nuisance to folks further north.
interesting westpac typhoon, with a northeastward moving storm banking left in the mid-latitudes under a strong ridge and forecast to recurve hard near eastern japan. bad storm if that verifies. the atlantic reflection would be a jeanne-type system. the atlantic might try to mirror that sort of pattern later on, though getting a storm to coincide with such a thing has long odds.
HF 0115z31august
| cieldumort |
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| Fri Aug 31 2007 02:45 AM |
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Re: surprise surprise
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TCFA is up on 96L now. Probably not too long for 94L now, either. While 96 is almost assuredly going to be nothing more than a Nova Scotia and/or out-to-sea bugger for shipping interests, 94 shows a lot of promise for those of us this side of Atlantic Standard Time.
If you ask me, the real story of the past 72 hours has really been the seemingly orchestrated chorus of increased activity from the west pac all the way out to the central Atlantic. Not catching much attention in the presses, but even waaaay north in the central Pacific an arguably "there" tropical cyclone formed near 30N, and an arguably "there" subtropical cyclone/gale came into form waaaay north up around 43N in the central Atlantic. Again, the common theme here has been a sudden and seemingly orchestrated pop in the activity all across the seaboards. While 92C in the north central Pacific and the subtropical gale in the north central Atlantic may, if they're lucky, garnish a footnote at the bottom of some annual 2007 summary, clearly WestPac Fitow, East Pac TD11 and probably TC-to-be 94L will use up much more ink than that.
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danielw
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| (Moderator) |
| Fri Aug 31 2007 03:32 AM |
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Re: surprise surprise
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94L, 96L and 97L are now up on the Site listed above.
NRLMY TCFA for 96L and others
| charlottefl |
| (Weather Hobbyist) |
| Fri Aug 31 2007 04:43 AM |
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Atlantic Activity
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Looks like we're on track for a season a little above average. In 2004 we were upto Frances at this point, making landfall Labor Day Weekend.
And wiith 94L looking like it has a good chance at a future we're looking at similiar #'s to 2004, at least upto this point. One thing that strikes me
kinda odd though it the difficulty storms have had in organizing the past 2 years. In 2004, and 2005 conditions seemed perfect for these systems
to pull together quickly and there has been a remarkable difference the last 2 years, and i'm just wondering what is having that effect.
| CoconutCandy |
| (User) |
| Fri Aug 31 2007 12:19 PM |
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Enter Felix, Stage Right
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Well, it certainly is beginning to look like the Hurricane Hunters will find a closed off low level center, with steadily lowering surface pressures. This one has TD and Storm written all over it.
It seems likely, IMHO, that there is no turning back now. While you've all slept overnight, I've been watching this little invest mushroom into something more than just a 'little invest'. (Remember, I am 6 hours behind Florida time)
Judging from the greatly increased aerial coverage and the intensity of convection, I'd hazard that surface pressures are beginning to lower. This is also evidenced by carefully observing the low-level inflow patterns. One can see a nicely defined cyclonic circulation, with long cumulus streets spiraling inward in all quadrants, and, where convection had been 'lacking/slacking' earlier in the E semi-circle previously, there are now several, short banding features blossoming out indicating a steady increase in organization, when all the convection works together to lower surface pressures, which in turn steadily increases the winds.
But of course, you all know this already. It's just always interesting, from a weather hobbyist perspective, to see it happening right before your eyes, time and again. Let's hear it for animated time-lapse satellite loops!
Additionally, there is also developing a central dense overcast CDO-like feature over the inner core convection, which usually bids well for an intensification surge.
Of all the current invests floating around, I'd place my bets, as has almost everyone it seems, on 94L to become TS Felix in the not-too-distant future. The TCFA has been out for some time now, the thermodynamic environment is becoming increasingly favorable and the 'negative' factors seem to be dwindling.
It'll be interesting to see what the Recon mission will reveal with regard to thermodynamic structure and wind fields.
And it'll be interesting, too, to see what becomes of the 'alleged' FAMCG (Far Atlantic Monsoon Cyclonic Gyre
), currently cycling within a large area SW of the Cape Verde, in the coming days and possibly weeks as it seems that the gyre might be setting up shop there for awhile.The latest tropical weather discussion (2am EDT, as I write) indicates " ...BROAD ELONGATED LOW / MID LEVEL CYCLONIC ROTATION COVERING THE AREA FROM 11N-19N BETWEEN 25W-36W WITH SEVERAL POSSIBLE ILL-DEFINED LOW LEVEL CIRCULATIONS.", which would be entirely consistent with the behavior of a monsoon cyclonic gyre, as discussed in the "Hurricane Ask/Tell" Forum. Pretty interesting stuff. Well worth a look.
Hold onto your hats and batten down the hatches, as it appears that "Ferocious Felix" will be the start to a quick succession of storms in the coming weeks, in a still yet predicted 'above average' total number of storms for the season.
| Beaumont, TX |
| (Storm Tracker) |
| Fri Aug 31 2007 12:22 PM |
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Re: Enter Felix, Stage Right
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Well, I've had faith in 94L since the beginning and it looks like he might be getting his act together this morning. NHC says a depression could
form later this morning. I wonder if we'll have Felix from this one.
| Unregistered User |
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| Fri Aug 31 2007 12:31 PM |
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Re: Tropics Acting Up Again
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94L soon to be Felix has continued to develope overnight and first visible shots show a build up of thunderstorms to the west of what looks to be a center and some developing to the north and east as well. I would expect to see at least a TD at 11am or maybe waiting for recon reports at 2pm. No matter I do believe Felix is on its way. As for the southern islands this will be a rain maker more than anything. I do believe this system will move w-nw over then next 24-48 hours into the central carribean. The diffrence with this system from Dean is the strong high to Dean's north is not there this time so a more northern direction is possible. How much is the question. A trough over the middle of the nation next week might open up the gulf for business so right now its too early to determin exactly how this will unfold. The disturbed weather east of the Bahamas may also play a roll as well as the approaching front off the east coast over the weekend. So theres alot to look at over the next few days as this system developes. Right now the southern islands need to get ready for possible heavy rain.
| doug |
| (Weather Analyst) |
| Fri Aug 31 2007 12:53 PM |
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Re: Tropics Acting Up Again
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Probably a TD for sure based on the signature it is making, and while there is still some SW-NE blow off, shear does not seem as pronounced as yesterday. Interesting synoptic pattern ahead of it. It looks like an "Omega" block over the Carribean which is not moving too much. I defer to the experts on that.
| cchsweatherman |
| (Weather Watcher) |
| Fri Aug 31 2007 01:06 PM |
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Re: Tropics Acting Up Again
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Good morning! Based upon my latest observations and the latest data from the Dvorak numbers and the NAVY website, it would almost appear certain that the NHC will upgrade 94L and 96L to Tropical Depressions by the 11AM update. 94L has caught my eye this morning as it appears to have begun to enter the favorable environment the NHC has been referring to over the past several days. About the potential future track of this system, I find it hard to believe that this will move in the same general direction as Dean due to the fact that there is a deep trough creating a large weakness in the high to 94L's north. Due to this fact, I would have to advice all the Greater Antilles to monitor this system. By the end of the day, I am expecting to see at least Tropical Storm Felix, if not Gabrielle also. I will be back around 11 for the next update.