MikeC
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| (Admin) |
| Wed Jun 09 2010 01:47 PM |
Central Atlantic Wave Being Watched
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5:43AM EDIT 16 June 2010
The wave in the Central Caribbean (92L) flared up overnight and satellite intensity estimations (dvorak t-numbers) are up higher than they have ever been, however upper level conditions are not favorable, and likely will destroy the system later today. There is a 10% chance that If the system persists like it has it could develop.
It will most likely continue moving westward as an open wave, without development.
6:58AM EDIT 15 June 2010
The wave in the Central Caribbean (92L) has persisted overnight, and for a while was looking better on satellite. This morning it appears to be losing some of the deep convection, and without it development won't occur. I expect the chances to fluctuate on an overall trend down slowly through the day for development, and most likely it will continue moving westward as an open wave, without development.
It is about to run out of time for development before running into shear.
6:50AM EDIT 14 June 2010
The wave (92L) is still holding together this morning, but not quite enough to support a tropical depression. It could form tonight or tomorrow if it continues to persist, and slowly organize like it has been. Models still do not have a very good handle on the wave. It is starting to gain some latitude as well. See Ed Dunham's take on the low latitude systems.. Invest 92L has a chance to join a short list of systems if it should attain Tropical Depression status while still below 10 degrees in latitude.
Convection is starting to organize around the center and consolidating. The overall large size it had yesterday is giving way to a more concentrated area.
With the consolidation it may adjust the apparent center slightly more to the north. This is another reason why the chances are still 60%. Once there is a clear center chances will go up. The condition of the upper air anticyclone relative to the low level center can also slow the development.
The window for development is today and tomorrow before conditions with shear will likely worsen.
Another wave exiting Africa (again, odd for the type in June) may be worth watching later as well, other wave opportunities will probably exist through next week as well.
The pattern this year is nearly opposite of the prevalent slow/weak development pattern of last year.
Those in the lesser Antilles will want to watch this system, but probably just for rainfall.
{{StormCarib}}
{{StormLinks|Invest 92L|92|1|2010|1|}}
8:00PM EDIT 13 June 2010
The wave in the Central Atlantic (92L) has persisted throughout the day and now has approximately a 60% chance for development into a tropical depression within the next 48 hours. It has short term conditions favorable for development, and it is projected to move mostly westward toward the Caribbean Islands, where shear may increase. Those in the Windward islands of the Caribbean will want to watch this system if it develops.
This is an unusual situation for June, so any development may not last very long.
9:00AM EDIT 13 June 2010
Signs of larger (or broader) area of low level circulation are starting to appear in the tropical wave known as 92L. Development chances may be closer to 40-50%. Movement of this area is generally toward the west around 9 mph.
The wave is over some abnormally warm water, but it still lacks the convection near the "center", roughly 7.6N / 34W. The overall flow is really large. It'll probably take another day to get wrapped in enough around the center to become a real candidate for development, if it does. Looking at water vapor imagery, It won't have that large of a window for development (see the elongation along the northwestern side of the area), which is probably the strongest reason it won't develop much, if at all. Still development chances are currently on an upward trend.
8:00AM EDIT 13 June 2010
The tropical wave in the southern Central Atlantic (92L), has not changed much overnight. Still about a 20-30% chance for development. If it persists through the day it may have a chance for development, but odds still are that nothing will occur with the system other than early season hype.
Leave a comment here if you have any thoughts on it.
There is a short term favorable environment for development, but this likely won't last long enough for the system to become organized. It does "look" good for a June system, however.
5:45PM EDIT 12 June 2010
Invest 92L is being tracked in the Atlantic, it is not likely to develop. This far east in June is rare, however.
92L is quite organized for this time in June, and is in an area of relatively low shear along with warm water temperatures. It likely will not last, but it still has about a 20-30% chance for development over the next few days as it moves westward. It is worth watching, but likely not to do much. It has no low-level circulation to speak of at the moment and models are a bit too early to believe.
If the system persists, chances for development may go up, but the more likely scenario of it not developing has climatology behind it. The very low latitude is also a factor against development.
Shear is likely to increase as it approaches the Windward islands, which will keep it in check. The short term factors seem, at first glance, seem like it may allow for development, but without a persistent low level circulation center it is too early to expect anything from this at all. Tomorrow will be telling.
8AM EDT 10 June 2010
The wave in the eastern Caribbean was sheared more than expected, enough to reduce chances of any development, even in the future. June remains mostly quiet.
Original Update
There is a tropical wave approaching the windward islands of the Caribbean that has no chance to develop in the short term, but as it enters into the central and western Caribbean shear begins to drop off and it has a chance to develop.
Worth this weekend into next week, but not in the near term. If anything occurs, it would likely just continue westward into Central America pr the Yucatan into Mexico, most likely as a rain event late next week. Rain in general across the Caribbean may be enhanced by this and a TUTT system.
What's odd about this particular wave is you usually do not see this type of wave until later July into August.
Other than this, there is not too much else going on, shear remains fairly strong in the Atlantic at least for now, but likely will start to fall off into July.
The water temperatures remain, in general, are a good deal warmer than last year at this time.
We'll be watching this wave over the next several days.
| LoisCane |
| (Veteran Storm Chaser) |
| Sun Jun 13 2010 04:49 AM |
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Re: Central Atlantic Wave Being Watched
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It's really low. Models do pull it north tho.
Normally, I wouldn't think this much on it but the size of it and the models are compelling.
Models have been consistently playing with waves and eventually one will turn into an early Atlantic TD.
http://cimss.ssec.wisc.edu/tropic/real-time/tpw2/natl/anim/latest72hrs.gif
Very low though.
| Storm Hunter |
| (Veteran Storm Chaser) |
| Sun Jun 13 2010 05:20 AM |
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Re: Central Atlantic Wave Being Watched
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just looked at the 00z data... very interesting to watch 92L... its very large and has protection to the north from the SAL...
Shear is near the islands... looking at the sats this evening... the wave is doing pretty nice for where its at for this time of year... GFS takes wave north of islands as high to north build again over the atlantic to its north... evening sats show nice banding in southern part of wave... if theres not a surface spin in there... it appears its not to far off... very impressive for this far out and this low in lat. I think tmrw will be interesting... i just don't see to much in the short term from not making this wave more healthier!
http://www.ssd.noaa.gov/goes/east/tatl/flash-rb.html
| cieldumort |
| (Moderator) |
| Sun Jun 13 2010 07:38 AM |
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Re: Central Atlantic Wave Being Watched
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Been keeping one eye out on this wave for quite a while now. By any measure, 92L is extremely robust for the location given the time of year - and it has been traveling in a cocoon of high water vapor content and relatively low shear for the better part of its exit from Africa. While a tight low level circulation does not look to have formed - yet - 92L appears to be embodied by a modest gyre (at least for the Atlantic basin) with a few embedded eddies or maxes.
In the very near term, the current low latitude trajectory should serve to both hinder and benefit. On one hand, there isn't going to be much in the way of any significant boost from the Coriolis effect that far south, but on the other, staying under 10-15 north keeps the system traveling over higher SSTs and out of detrimental shear.
It seems reasonable to conclude that a significant window for further development is open through at least the next 24 to perhaps as many as 72 hours. After that, if 92L has not yet developed a solid inner core, either some potential interactions with land/near land effects, or a run in with increasing shear and dry air from its north/northwest, could put a stop to any further development for at least a day or few.
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danielw
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| (Moderator) |
| Sun Jun 13 2010 12:21 PM |
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Re: Central Atlantic Wave Being Watched
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NHC has bumped up the chance for development to 30% at 8 AM EDT.
Rather tough looking system for June 13th...
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MikeC
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| (Admin) |
| Sun Jun 13 2010 12:45 PM |
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Re: Central Atlantic Wave Being Watched
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If it keeps up today, it has a better chance tomorrow. I'm finally seeing some broader signs of a low level circulation. Right now though it's still leaning against it. (Although chances may go up to 30-50% later today if the low level circulation takes hold)
| marco67red |
| (Registered User) |
| Sun Jun 13 2010 01:31 PM |
Re: Central Atlantic Wave Being Watched
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Good morning ...
Not trying to be nit-picky, but thought I'd mention what I'm thinking is a typo in the 9am post -
Are you actually discussing 92L in the following?
>>9:00AM EDIT 13 June 2010
Signs of larger (or broader) area of low level circulation are starting to appear in 90L. Development chances may be closer to 40-50%. Movement is generally toward the west around 9 mph <<
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MikeC
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| (Admin) |
| Sun Jun 13 2010 01:40 PM |
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Re: Central Atlantic Wave Being Watched
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Fixed, thanks for the mention.
The wave is over some abnormally warm water, but it still lacks the convection near the "center", roughly 7.6N / 34W. The overall flow is really large. It'll probably take another day to get wrapped in enough around the center to become a real candidate for development -- but I'm not sold. One positive factor for development is it's pretty wet, no real dry air around it. The models are interesting on it, GFS is on the weak side, NOGAPs tends to be stronger. The SHIPS intensity model is a bit too much right now.
Looking at water vapor imagery, It won't have that large of a window for development (see the northwestern side of the area), which is probably the strongest reason it won't develop much if at all.
| CoconutCandy |
| (User) |
| Sun Jun 13 2010 02:12 PM |
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Invest 92L Appears To Be Organizing Better
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Excellent discussions this morning, as usual !!
Yes, this is certainly an interesting development in this region for this time of year, as 'Cape Verde Systems' don't get going here until the first part of August, climatologically speaking.
During the overnight hours, there appears to have been a steady increase in the amount and extent of convective activity associated with this system, and moreover and more recently, although convection is warming somewhat, it appears that it's becoming better organized, and this Invest is now beginning to take on a rather 'healthy looking' appearance, as suggested by this animated visible satellite imagery.
Looking carefully at this animation, I'm noticing the beginnings of what might be considered convective banding features, with discernible arced shaped banding wrapping around in the northern quadrant of a broad 1012 mb low, and a much longer, yet more linear feature, being drawn into the developing circulation from the WSW.
Although convection is not quite as deep, with slightly warmer cloud tops, as compared to the overnight hours, this is rather typical during daylight hours, presumably because of the so called 'diurnal convective minimum' cycle, owing to the slightly warmer ambient temperatures at cloud top levels. Tonight should be rather telling, however, and we should expect to see a dramatic increase, again, of the type of sustained, deep, bursting convection that occurred last night.
Also becoming noticeable this morning is a slow NW'ward movement of the overall circulation envelope, which now appears to be crossing over 35 W longitude, near 7 degrees N, as model guidance is beginning to suggest, now that several runs have been compiled. Model consensus is rather clustered towards a general WNW or NW motion through the next few days, unfortunately tracking it right towards the Caribbean Windward Islands, or Lesser Antilles.
As mentioned previously, the probability of this Invest becoming a tropical cyclone in the next 48 hours has been increased to 30%, and the latest (8am EDT) tropical weather discussion from the TPC / NHC has begun to refer to this system as a "Special Feature".
A BROAD AREA OF LOW PRESSURE FOCUSED ON A 1012 MB SURFACE LOW IS CENTERED NEAR 07N34W IN THE CENTRAL TROPICAL ATLANTIC ... THE UPPER AND LOWER LEVEL ATMOSPHERIC CONDITIONS IN THE VICINITY OF THE LOW CONTINUE TO EXHIBIT FAVORABLE CHARACTERISTICS FOR CONTINUED ORGANIZATION OVER THE NEXT COUPLE OF DAYS.
And as the last few TPC tropical discussions have mentioned, the broad surface low appears to be following the westward propagating wave axis, in a field of high preciptable water content and low upper level wind shear, both conducive and essential for tropical cyclogenesis to occur.
A LARGE AREA OF DEEP LAYER MOISTURE IS NOTED IN THE TOTAL PRECIPITABLE WATER IMAGERY THIS MORNING EXTENDING FROM THE EQUATOR TO 11N BETWEEN 25W-41W. THE MOISTURE AND INSTABILITY SURROUNDING THE LOW IS GENERATING NUMEROUS MODERATE AND SCATTERED STRONG CONVECTION.
ALOFT, AN UPPER LEVEL ANTICYCLONIC CIRCULATION IS CENTERED OVER THE CAPE VERDE ISLANDS ... AND UPPER LEVEL DIFFLUENCE ASSOCIATED WITH THE (ASSOCIATED) UPPER LEVEL RIDGE IS HELPING TO VENTILATE CONVECTION AND SUSTAIN LIFT IN THE SURFACE TO MID-LEVEL CYCLONIC CIRCULATION.
In short, IMHO, this strong tropical wave has a lot going for it, with SHIPS Intensity guidance nearing hurricane strength in 36 hours from the last model run, which seems rather high, and presumably due to the expected redevelopment of deep, bursting and cycling convection near and over the nascent LLC center in the upcoming overnight hours, when the diurnal convective maximum will be at it's greatest, and the possible development of a CDO feature over the LLC.
I, for one, am more bullish on development of this system, at least in the short term, than some here for these reasons:
1) A broad, low level circulation with an embedded 1012 mb low is already well established.
2) Very high values of precipitable water are over a large area for the convection to work with.
3) Very low upper level wind shear is over and ahead of it's expected track, at least short term.
4) A well established upper level ridge overlying the area, providing for good diffluence aloft.
5) No foreseeable entrainment of dry air at low or mid levels and well buffered from the 'SAL layer', further north.
6) Very warm, anomalously high SST's over a broad area, and it's associated higher 'Oceanic Heat Content' value.
7) The apparent recent nascent development of a discernible Low Level Circulation Center.
8) And finally, the apparent increase of 'banding features' associated with this developing circulation.
I think the next Tropical Outlook, due out in a couple hours, might maintain the system as is, for now, considering the convective warming trends we've seen during today's daylight hours. But with all it has going for it, I fully expect to see this system consolidate during tonight's convective max, and we may well be looking at the Atlantic's first tropical cyclone of 2010, Tropical Depression ONE, by sometime tomorrow. This should prove to be very interesting!
...
| Hugh |
| (Senior Storm Chaser) |
| Sun Jun 13 2010 02:38 PM |
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Re: Invest 92L Appears To Be Organizing Better
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Quite impressive to have a quasi-Cape Verde storm even with a possibility of developing in the middle of June.
Convection seems to have warmed a bit over the last several hours. I'd say 30% chance may be generous. The visible loop does show the beginning of a LLC, though. If that holds together for the next day or two, it's probably going to get organized enough by then to be classified. Models are a bit disturbing in putting this thing through the islands.
| Unregistered User |
| (Unregistered) |
| Sun Jun 13 2010 03:27 PM |
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Re: Invest 92L Appears To Be Organizing Better
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Center is near 6.7N and 36.1W as I type this. Pressure near 1010mb moving just north of due west @ 13mph.
Overall it looks likes its getting better organized...Now we need to see T-Storms develop and sustain near the COC. Probably by Monday or Tues once it gets to near 10N
| scottsvb |
| (Weather Master) |
| Sun Jun 13 2010 03:30 PM |
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Re: Invest 92L Appears To Be Organizing Better
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Forgot to login above.
Models are not picking up on this so far...(with TS development) Probably shear north of 18N will hinder development some...also rising pressures in the Atlantic. It does have a decent chance if it stays below 17N thru this week.
| MichaelA |
| (Weather Analyst) |
| Sun Jun 13 2010 05:18 PM |
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Re: Invest 92L Appears To Be Organizing Better
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Rather impressive looking for this early and so far East. If it does develop into a classified tropical storm, it may be a harbinger of things to come this season - not good. So far, it is already August hot here on the Gulf coast of Florida.
| Hugh |
| (Senior Storm Chaser) |
| Sun Jun 13 2010 05:29 PM |
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Re: Invest 92L Appears To Be Organizing Better
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Quote:
Rather impressive looking for this early and so far East. If it does develop into a classified tropical storm, it may be a harbinger of things to come this season - not good. So far, it is already August hot here on the Gulf coast of Florida.
There are some Augusts that aren't THIS hot, in fact.
I just pulled up the floaters, and now the spin is clearly evident on both the visible and AVN loop. It's getting close to "code red" on the NHC's probability chart (>50%), I'd guess (45% seems about right, in other words).
The BAM models do not paint a pretty picture at all for the long-term outlook... putting it straight through the Caribbean, at least straight through the Lesser Antilles. Someone check the calendar - it IS June 13th, right?
Update: The 2pm TWO does indeed put the system on the brink of "code red"... with a 50% probability of development during the next 48 hours.
| typhoon_tip |
| (Meteorologist) |
| Sun Jun 13 2010 11:35 PM |
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Re: Central Atlantic Wave Being Watched
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NHC has as of 2PM elevated their probability to 50% and I feel rightfully so. It is important not to be hung up on climatology; climate does not dictate what any given event will do, but is cumulative result of many seasons, then normalized.
SSTs
As others have gone great strides to point out and is common knowledge at this point, the SSTs in the region between the Puerto Rico archipelago and Africa are in +AMO.
SAL:
There does not appear to be any SAL toxicity in the vicinity of the ingest regions for the zygote cyclone. There is some SAL related material observable here: http://cimss.ssec.wi...vetrak/sal.html ...but this is consistent with normal background contaminant - it would appear - and not directly associated with the burgeoning circulation of the system, either.
Deep layer shear:
Nearly non-existent at this time when studying the upper most elevation wind overlay at NHC's satellite website: http://www.ssd.noaa..../flash-avn.html The mlv cut is difficult to ascertain because cloud tags are used to determine vectors and they are obscured by a fairly healthy U/A anvil debris field; therefor, have to rely on modeling (as far as I am aware) to determine if there is a pesky intervening layer of shear.
Madden-Julian Oscillation related tropospheric tendency :
Currently the Atlantic Basin et al is in a neutral-positive 200mb anomaly state, http://www.cpc.ncep....m_monthly.shtml, which lay-term is usually conducive to sustaining, not compensating, for upward vertical motion in ambient field. Any system on the rail service between African and the western Basin would avail of that circumstance.
Integrated energy:
The circulation envelopes a huge area. Larger systems tend to spin up slower. However, given to their immensity they are somewhat more resistant to negative impacts. It all really comes down to momentum and larger systems having more of it, but there are also papers that discuss why in more technical terms.
I have not spent much time looking at models, but unless they are parameterized deliberately I can't imagine they would to exceptionally well until such time as the system is initialized in the input more sufficiently.
John
| Hugh |
| (Senior Storm Chaser) |
| Sun Jun 13 2010 11:52 PM |
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Re: Central Atlantic Wave Being Watched
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Quote:
NHC has as of 2PM elevated their probability to 50% and I feel rightfully so. It is important not to be hung up on climatology; climate does not dictate what any given event will do, but is cumulative result of many seasons, then normalized.
As of 8pm, it's now a code red, 60%. Based upon current satellite presentation trends, I expect we will have TD One by the 11am advisory package tomorrow, if not before.... IF the organization trend continues.
| Clark |
| (Meteorologist) |
| Mon Jun 14 2010 12:12 AM |
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Re: Central Atlantic Wave Being Watched
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Formation locations and tracks of all June North Atlantic tropical systems, 1851-2009. The furthest east was Ana in 1979, forming at 45.0°W. The furthest south was the second storm of 1933, forming at 8.8°W. Invest 92L, currently at 7.0°N and 35.5°W, would eclipse both records were it to form in the next day or so. Source: NOAA Coastal Services Center.
| weathernet |
| (Storm Tracker) |
| Mon Jun 14 2010 07:15 AM |
Re: Central Atlantic Wave Being Watched
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Wow......., what an interesting year this might turn into.
Though the NHC 2:00 a.m. read as follows
...... "HAS CHANGED LITTLE DURING THE PAST SEVERAL
HOURS. HOWEVER...ENVIRONMENTAL CONDITIONS ARE EXPECTED TO REMAIN
CONDUCIVE FOR ADDITIONAL DEVELOPMENT...."
I certainly cannot help but see a marked improvement in the overall consolidation of convection. The anticipated diurnal processes at hand, not only has there been an increase in center co-located convection, but am seeing a classic wrap around hook beginning to take place on the west side of what appears to be an evolving and better defined center. Furthermore, I would argue for increasing evidence of the start of some banding features coming in from the south. Whether or not a special advisory is issued for this system during these early hours, is mute at this point. However given the increased convection within such an envelope system, and without any immediate impending UL shear, as far as I am concerned we have a bona-fide depression out there. If in fact a true core consolidation is finally taking place with this large system, than not only might the "up and down" pulsating cease, but I would be frankly surprised if we did not have our first named TS during the next 24 hours.
Frankly, I am less in awe of such an eastern forming tropical cyclone in June, or the conditions already at hand aiding in this systems development. Mostly, I can't get over the size and maturity of such a tropical wave, so early and so far east. For the most part, we are all assuming this Atlantic Hurricane Season to be busy. Perhaps a greater number of storms to be strong ( if for no other reason than the potential increase in over all activity ). However, might this early large envelope tropical system be also indicative of the greater majority of this seasons tropical systems? I vaguely recall Ana from 1979, being the first storm that season and yet forming pretty far to the east, yet if memory doesn't fail me ( though it might! ) I seem to recall it being a fairly small system. Only time will tell what the MOST critical concern will be - "WHERE" will the predominant tracks take this years systems. Though not stamped in stone, I believe history has shown that larger tropical cyclones ( despite potentially feeling greater impact by the Coriolis effect ) tend to often have longer tracks with less polar bias.
One final oddity regarding 92L, or at least one to me. During most Hurricane Seasons, one long range model or another ( usually GFS ), typically dishes up a number of "ghost storms". Tropical systems that for days, are forecast to develop, only to show up perhaps as a wave, and then simply dissipate. This year we already are aware of foreboding SST's and the much advertised demise of El Nino. Yet despite this, certainly no real overly aggressive and deep systems yet forecasted by long term models. In fact, perhaps only NOGAPS ( ironically conservative ) to have hinted towards this current system. My recollection is that most longer range models would far easier pick up more accurately on such larger and more organized waves. So, it just strikes me as curious that such a larger "Cape Verde" type envelope system develop so easily materialize and develop ( given climatology ), yet without the more typically anticipated "modelcane" being well advertised well in advance.
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MikeC
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| (Admin) |
| Mon Jun 14 2010 10:51 AM |
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Re: Central Atlantic Wave Being Watched
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The wave (92L) is still holding together this morning, but not quite enough to support a tropical Depression. It could form tonight or tomorrow if it continues to persist, and slowly organize like it has been. Models still do not have a very good handle on the wave. It is starting to gain some latitude as well.
Another wave exiting Africa (again, odd for the type in June) may be worth watching later as well.
The pattern this year is nearly opposite of the prevalent slow/weak development pattern of last year.
| Hugh |
| (Senior Storm Chaser) |
| Mon Jun 14 2010 11:46 AM |
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Re: Central Atlantic Wave Being Watched
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I gotta say, Mike... this is the best looking non-TD I've seen in a long time.
Nice banding features, decent outflow... convection near the obvious LLC.
What exactly is missing? It looks better than what have sometimes been classified as
tropical storms.
8am TWO just released... basically no change to the wording. Still 60%. Looking at the satellite presention right now, I'd put it closer to 80%, personally.
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MikeC
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| (Admin) |
| Mon Jun 14 2010 12:06 PM |
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Re: Central Atlantic Wave Being Watched
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It looks like it will by tonight (could be the afternoon). I'd like to see better Dvorak T Numbers than what it has, it's trending toward that way, but not quite there yet. Convection is starting to organize around the center/consolidating, and the overall large size is giving way to a more concentrated area. Also lack of QUIKSCAT this year is hurting for systems like this.
With the consolidation it may adjust the center slightly more to the north. This is another reason why it's still 60%. Once there is a clear center the game is on. (Best track has it at 9.7N 39.9W)
I'm a lot harder on this system than I otherwise would be because of the calendar. That and conditions out ahead of it still will likely cut it to pieces. There are some hints on satellite imagery that shear may venture into it more (especially if it forms more north).
| Hugh |
| (Senior Storm Chaser) |
| Mon Jun 14 2010 12:57 PM |
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Re: Central Atlantic Wave Being Watched
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Quote:
It looks like it will by tonight (could be the afternoon). I'd like to see better Dvorak T Numbers than what it has, it's trending toward that way, but not quite there yet. Convection is starting to organize around the center/consolidating, and the overall large size is giving way to a more concentrated area. Also lack of QUIKSCAT this year is hurting for systems like this.
What happened to QUICKSCAT? Apologies if it's common knowledge, I wasn't aware that it didn't exist this year.
Navy has issued a TCFA. Ironically, now that the sun is up, it DOESN'T look as much on the verge of being a TD as it did with just the infrared images... although the floater is no longer over the system exactly - hopefully they'll move it soon. There's a big blowup of convection northeast of the LLC, so maybe it will reform there.
Time to dust off my "Favorites"
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MikeC
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| (Admin) |
| Mon Jun 14 2010 01:02 PM |
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Re: Central Atlantic Wave Being Watched
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For Quikscat, The main sensor on the satellite died on November 23rd, although it was deteriorating earlier in the season. They couldn't restart it, so the Quick Scatterometer is gone. I think there is a replacement with better tech scheduled for launch in 2015, but until then that semi-detailed wind data for remote storms just won't be there.
Quikscat usefulness vs cost was debated, but it's obvious in situations like 92L it could be beneficial. Besides wind estimates, it did wave heights, sea ice estimation, assisted with aviation weather, iceberg movements, and helped quite a bit to determine the state of El Niño.
There still is the ASCAT though, but that's only a shadow of what QuikScat had.
| MichaelA |
| (Weather Analyst) |
| Mon Jun 14 2010 03:37 PM |
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Re: Central Atlantic Wave Being Watched
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92L doesn't look quite as impressive in the latest vis pics. Shear taking a toll on this system already? Smaller aerial coverage with tops blowing off to the North. Some convection seems to be trying to form in the SW quadrant, though. If that persists, 92L will still have some chance to continue to develop. Whatever happens, having something trying to spin up that far East and South this early in the season, is unusual and may herald the predicted very active season ahead. It is really far South to be this well developed, too - about 10° N now and seems to be heading more NW.
| cieldumort |
| (Moderator) |
| Mon Jun 14 2010 04:05 PM |
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Re: Central Atlantic Wave Being Watched
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92L appears to have consolidated somewhat under the deeper convection of the very late overnight and this morning. Positions still carrying the cyclone at anywhere under 10N are probably quite obsolete at this point, as the center of 92L is now traveling along and/or within deeper convection, and perhaps already somewhere in the vicinity of 10.5 to 10.8 N and 40.1 to 40.5 or so W.
As of 1500 UTC, 92L now resembles in many ways many of those short-lived tropical depressions or weak tropical storms of the central Pacific. I think that it is regrettable that QS is no longer online, as this could very well perhaps by now have confirmed the existence of a primary, satisfying llc. 92L sure looks as close to "there" as I have just about ever seen. Convection is maybe still a bit wanting, but I've certainly seen worse on other systems befitting of the title.
Dr. Rick Knabb, now TWC's tropical expert (replacing Dr. Steve Lyons who has gone back to work for the NWS), was on just a little while ago opining that there is little to no shear ahead of 92L. I find that statement a bit puzzling, as it appears that 92L is already starting to feel the first bites of increased shear and a little less precipitable water, and that a zone of much higher shear and drier air exists not far to its north and northwest (up ahead), and while some models want to lift the trof imparting that shear, model shear forecasts also do not guarantee that will go away any time in the very near future - at the rate 92L is traveling interaction with this razor could easily occur before any such lifting away of the shear takes place.
Should the trof indeed pull up and allow 92L to remain coddled within its envelope of low shear and high water vapor content, the outlook for the islands later this week or next could get worrisome.
| Storm Hunter |
| (Veteran Storm Chaser) |
| Mon Jun 14 2010 08:29 PM |
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Re: Central Atlantic Wave Being Watched
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Clearly the low at the center is much better organized now... smaller center then the broad center we have been seeing for a few day... i'm still skeptical why the call is not made to at Tropical Depression now... Vis sats. clearly show a surface low. Shear is not to far off to the NW... and i would expect tonight to see some decent covection tonight if the shear doesn't affect to outflow channels... This evening will be interesting... if the system will hold or weaken...
| Hugh |
| (Senior Storm Chaser) |
| Mon Jun 14 2010 09:01 PM |
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Re: Central Atlantic Wave Being Watched
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It looks pretty sick right now... getting shredded to pieces, in fact. The NHC called it right after all. It could still overcome shear I suppose, but I'd say it's missed the best chance it has.
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MikeC
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| (Admin) |
| Mon Jun 14 2010 10:18 PM |
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Re: Central Atlantic Wave Being Watched
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The development chances are on rapid decline, it looks it tried to move too far north and started running into the shear earlier than expected.
| Hugh |
| (Senior Storm Chaser) |
| Tue Jun 15 2010 12:37 AM |
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Re: Central Atlantic Wave Being Watched
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Quote:
The development chances are on rapid decline, it looks it tried to move too far north and started running into the shear earlier than expected.
And, just as we say that, convection appears to have picked back up over the LLC. It's still got a 40-50% shot I'd say.
| jessiej |
| (Weather Watcher) |
| Tue Jun 15 2010 12:46 AM |
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Re: Central Atlantic Wave Being Watched
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If you look at the intesity forcast, it seems it will make it into the Carribean and rapidly strengthen.
| Joeyfl |
| (Weather Guru) |
| Tue Jun 15 2010 01:22 AM |
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Re: Central Atlantic Wave Being Watched
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I would not write this low off yet, while its a rough road ahead it still has chance in latest ir satellite shows a flar up of convection near center with 10-20 knot shear.
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Ed Dunham
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| (Former Meteorologist & CFHC Forum Moderator (Ed Passed Away on May 14, 2017)) |
| Tue Jun 15 2010 02:11 AM |
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Re: Central Atlantic Wave Being Watched
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While it is true that the Invest area has seen a recent flareup of convection, the overall structure of the system has not shown the development necessary for classification as a tropical cyclone. The general appearance is still ragged and lacks organization. Regarding intensity, here is the latest output of the low-level model suite from NHC:
DISTURBANCE INVEST (AL922010) 20100615 0000 UTC
...00 HRS... ...12 HRS... ...24 HRS. .. ...36 HRS...
100615 0000 100615 1200 100616 0000 100616 1200
LAT LON LAT LON LAT LON LAT LON
BAMS 11.3N 42.1W 12.3N 44.6W 13.3N 47.1W 14.2N 49.5W
BAMD 11.3N 42.1W 12.6N 44.2W 13.8N 46.0W 14.8N 47.5W
BAMM 11.3N 42.1W 12.3N 44.4W 13.4N 46.5W 14.2N 48.5W
LBAR 11.3N 42.1W 12.9N 44.4W 14.4N 46.8W 15.7N 49.1W
SHIP 25KTS 26KTS 28KTS 28KTS
DSHP 25KTS 26KTS 28KTS 28KTS
...48 HRS... ...72 HRS... ...96 HRS. .. ..120 HRS...
100617 0000 100618 0000 100619 0000 100620 0000
LAT LON LAT LON LAT LON LAT LON
BAMS 15.1N 51.9W 16.8N 56.8W 18.5N 61.6W 19.8N 66.3W
BAMD 15.5N 48.6W 16.3N 50.9W 17.0N 53.4W 17.7N 55.3W
BAMM 14.9N 50.4W 16.2N 54.4W 17.4N 58.0W 18.4N 61.3W
LBAR 16.8N 51.2W 19.1N 54.6W 21.9N 56.9W 23.9N 59.0W
SHIP 29KTS 30KTS 28KTS 22KTS
DSHP 29KTS 30KTS 28KTS 22KTS
These latest track forecasts would all move a very weak system to the north of the Caribbean Islands. Looking at the windshear forecast
Unisys 48hr Windshear Forecast
and the forecast points, the system has until about 17/00Z (a couple of days) to regenerate and develop before it encounters a zone of stronger windshear. It is fair to note that the zone of shear is anticipated to be on the decline in the 36 to 72 hour timeframe, and it is also fair to note that model intensity forcasts are seldom very accurate.
ED
| Storm Hunter |
| (Veteran Storm Chaser) |
| Tue Jun 15 2010 05:55 AM |
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Re: Central Atlantic Wave Being Watched
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hmm... see the 2am TWO now back to 50%... the overall structure at the surface and mid levels is getting better... but appears to me that the upper levels are causing the problems... it appeared that some drier air was "sucked" into the system yesterday on the southern side of 92L and caused some problems... appears there still about 20mph shear overhead... but more and stronger is ahead... before it appears that it should begin to weaken in about 48-72 hrs.... still trying to figure if this will go into carb or go north of islands... leaning towards an entrance into carib. as of the 00z data i have seen... will be interesting to see what happens today... as TWO states this could become a Tropical Depression later today... time will tell
I still think 92L is very close to TD status if not a TD in its organization. Clearly a center can be found on a Shortwave IR
http://www.ssd.noaa.gov/goes/flt/t1/flash-ir2.html
| cieldumort |
| (Moderator) |
| Tue Jun 15 2010 07:20 AM |
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Re: Central Atlantic Wave Being Watched
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In just about any practical sense, 92L has straddled the line several times over the last 36, to maybe 48 hours, or so. Given that NHC likes persistence when they make a call, this fickle nature may have been enough to keep them conservative for a system so far out in the Atlantic, well-removed from any buoys, boats, and such.
The most recent "night vision" shortwave IR images have been suggesting that the llc has been getting much better defined, once again, and taken with a recent AMSU pass (see below) one could argue that the llc and MLC are pretty well linked up, and that sufficient convective banding has taken place.
But, once again... persistence. Must ... wait ... wait ...
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danielw
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| (Moderator) |
| Tue Jun 15 2010 04:10 PM |
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92L and GOM?
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While I don't recall seeing a better satellite photo of the LLC and MLC being stacked in the vertical I'll admit that 92L is staying under the radar , or "straddling the line" as you said. Lower level of development would lend to a closer approach of the system to the Lesser Antilles. It would also give the models a rough time with forecasts.
Closer to home. A weak trough in the Bay of Campeche appears to be consolidating. Yesterday's visible indicated a vortice on the western edge of the system. Presently there is a central area of thunderstorms and three strange looking bands separated by nearly 120 degrees around the system.
http://www.ssd.noaa.gov/goes/east/gmex/loop-jsl.html
I'll call it a trough at this point after looking at the loop. It's definately an area to watch as the BOC is one of the preferred areas for June development... normally.
| hogrunr |
| (Weather Guru) |
| Tue Jun 15 2010 06:26 PM |
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Re: 92L and GOM?
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Mark Sudduth over at Hurricanetrack mentioned the spot in the BOC yesterday in his weekly hurricane discussion video, and being that I am close to the Texas coast it sparked my attention. At the time the system was just coming off shore of Mexico, but since then, the convection has really exploded and stayed that way. It is hard to tell at this point whether the small circulation is still there or not, but the bands are certainly evident. It is currently sitting just between two areas of high shear (20-30 knots), so it is in a good spot for most things needed for development (low shear, high heat content). However, depending on the movement of the areas of shear that are currently surrounding it are, it could very easily turn out to be nothing.
CIMSS Wind Shear
As mentioned by the NHC:
...DISCUSSION...
GULF OF MEXICO...
WATER VAPOR IMAGERY SHOWS A NEAR STATIONARY UPPER LEVEL LOW OVER
THE FAR SOUTHWEST BASIN. THIS UPPER LEVEL FEATURE IS INTERACTING
WITH A SURFACE TROUGH ANALYZED FROM 25N92W SOUTHWEST TO NEAR
18N95W. SCATTERED MODERATE TO STRONG CONVECTION IS SOUTH OF 26N
BETWEEN 90W AND 97W. COMPUTER MODELS INDICATE THIS AREA OF
CONVECTION WILL LINGER NEAR THE SAME REGION WITHIN THE NEXT 24
TO 36 HOURS.
| Storm Hunter |
| (Veteran Storm Chaser) |
| Tue Jun 15 2010 07:31 PM |
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Re: 92L and GOM?
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92L is taking a beating by the shear now... based on sats... appears the shear is affecting the whole system now... from south to north... until the relaxes... 92L will have a hard time developing into anything.
| cieldumort |
| (Moderator) |
| Tue Jun 15 2010 08:11 PM |
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Re: Central Atlantic Wave Being Watched
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The approximate center of 92L (roughly 13.3 N 46 W as of this entry) is currently passing to the south of
Buoy 41041 (located at 14.357 N 46.008 W). Pressures at the station 41041 have fallen at a slow rate, and maximum 1-min sustained winds have thus far reached a peak of at least 35 MPH at an elevation of 5 meters above sea level, and have generally been a range of 15-30 MPH this afternoon. A slight wind has shift occurred, shifting from mostly east to mostly ene, and now back to east, suggesting either a very small closed circulation (if one still exists), but more likely 92L is now once again an open wave, as also suggested by its appearance in visible satellite images.
The weak remains of this cyclone which will remain nameless could be of some concern late this week or next should it manage to hang in there until a potential sweet spot opens up for it - at this time the most likely location/s for improved chances of development could be the western Caribbean or GOM - next week if it survives till then - and all pure speculation at this point, but something to watch for.
Elsewhere, disturbed weather in the Bay of Campeche mostly had to do with an ULL interacting with a surface trof together dragging up some deep moisture from the tropics. Surface pressures have not been falling, and there is probably only a small chance at best for tropical cyclone development in that region over the near term.
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danielw
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| (Moderator) |
| Tue Jun 15 2010 11:54 PM |
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Re: Central Atlantic Wave Being Watched
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Buoy 41041 pressure bottomed out about 3 hours ago. Appears to be a diurnal cycle. But the winds have increased to 23 kts gusting to 31 kts. Seas are up to 12 ft and wind direction is back to SSE.
Beats me, unless the center reformed in a different location. Compared to yesterday. Winds nearly double on sustained and gusts. Barometer is down 0.05 inches. Dominant wave period is at 9 seconds.
Nice to know that someone else is watching the back door... GOM.
Hard to ignore, as the dreamsicle IR loop is at the bottom of the screen on the Weather Channel. Any cyclonic curvature of the clouds in the GOM will raise an eyebrow this time of year.
WV GOM loop still indicating the ML or UL LOW is centered offshore of Veracruz,MX. Pockets of convection rotating around the S and E side of the Low. Mostly cyclic convection.
| hogrunr |
| (Weather Guru) |
| Wed Jun 16 2010 12:14 AM |
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Re: Central Atlantic Wave Being Watched
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Wow...the shear that was present around the area in the GOM has all but disappeared this afternoon. It was surrounded by 20-30 knot shear and that has relaxed dramatically. This are may become nothing, but I think that it has all of the setup to become something of importance very quickly.
| cieldumort |
| (Moderator) |
| Wed Jun 16 2010 03:01 AM |
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Re: Central Atlantic Wave Being Watched
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As for tropical cyclone development, I think the GOM looks pretty much benign through at least the next 48 hours. Upper level winds are simply unfavorable for development at this time, despite the existence of at least two surface features, bountiful moisture, and very toasty SSTs. However, scattered to widespread showers and thunderstorms will probably be ongoing, off and on.
I wanted to chime back in on 92L for a moment - Systems like this... often never a good idea to write them off too fast. And judging by the first real buoy data on this feature, taken at a time when it had already been significantly diminished and disrupted by shear and dry air, it looks that 92L very well may have been blowing at or (probably) even above 35 knots for a good while when the surface circulation was almost definitely closed off during the overnight last night and early this morning.
Now tonight, it does appear that the trof which had been imparting so much shear above 10-15N is lifting out a little, and weakening some. Also, because 92L has traveled along with such a massive plume of deep moisture, the dry air which had started to get injected into the system throughout the day Tuesday, looks to be getting pushed back to the west, as 92L advances.
Most recently, very deep convection has blown back up over at least the northern semicircle, probably in no small part fanned by the increased southwesterly shear. This level of increased shear can sometimes actually enhance tropical cyclone formation (think of blowing on a smoldering pile of leaves and needles, so as to get a fire started), and I believe that, at least at the moment, we are witnessing this tonight.
Stay tuned...
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Ed Dunham
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| (Former Meteorologist & CFHC Forum Moderator (Ed Passed Away on May 14, 2017)) |
| Wed Jun 16 2010 03:43 AM |
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Re: Central Atlantic Wave Being Watched
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"Systems like this ... often never a good dea to write them off too fast" seems to be indeed good advise when it comes to 92L. Excellent regeneration of convection this evening in its diurnal cycle. The southwesterly shear probably is enhancing the convective development and the shear zone itself is breaking down about 24 hours earlier than initially expected. SSEC University of Wisconsin suggests that the zone may be relocating further to the south:
SSEC 24hr Windshear Change
My best guess position estimate for 16/02Z was 14.3N 47.8W with movement still west northwest to northwest.
ED
| Lamar-Plant City |
| (Storm Tracker) |
| Wed Jun 16 2010 04:24 AM |
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Re: Central Atlantic Wave Being Watched
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That convection flair-up is VERY impressive tonight. I had not expected that from this system. So the SW shear is encouraging the convection.....is that because it is night time? Will this same shear tear it down tomorrow? This system has been intriguing from the outset, but seems to not want to die despite the NHC's best efforts at wishing it away!
| Storm Hunter |
| (Veteran Storm Chaser) |
| Wed Jun 16 2010 04:51 AM |
| Attachment |
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Re: Central Atlantic Wave Being Watched
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Very impressive... i noticed this evening there was a lot of spanding with moisture in the mid levels near and around this low.... it appears that there very low shear over the area right now... atleast for the last 4-6 hrs.... almost perfect upper level anticyclone outflow in all directions... and warm temps are increasing in the area...
i think the surface "center" of the low is near the red dot in my image... on the sw side of the deep convection... it almost appears there is a mid level center trying to catch up with the surface center?
it still appears to me the stronger shear is just right down the road...
| rmbjoe1954 |
| (Weather Master) |
| Wed Jun 16 2010 12:36 PM |
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Re: Central Atlantic Wave Being Watched
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92L is feisty and tenacious and has shown resiliency. The shear it will encounter will most likely end any possible concentrated circulation to what appears to be the beginning of a very active season. The remains of 92L would most likely end up as an open wave in the Bahamas and South Florida.
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danielw
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| (Moderator) |
| Wed Jun 16 2010 01:20 PM |
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Re: Central Atlantic Wave Being Watched
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Note
Thumbnail of 92L on left sidebar is not updating. Neither is the weblink at CIMSS.
Upper left corner thumbnail is current.
| doug |
| (Weather Analyst) |
| Wed Jun 16 2010 03:17 PM |
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Re: Central Atlantic Wave Being Watched
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looks like it has just run into a brick wall. The west half has flattened and the circulation there is being impeded. Shear should do this in today, IMO
| Unregistered User |
| (Unregistered) |
| Wed Jun 16 2010 04:06 PM |
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Re: Central Atlantic Wave Being Watched
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What are the chances that 92L survives the shear and becomes a tropical depression? On satelite right now 92L looks like a depression.
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MikeC
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| (Admin) |
| Wed Jun 16 2010 04:15 PM |
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Re: Central Atlantic Wave Being Watched
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Quote:
What are the chances that 92L survives the shear and becomes a tropical depression? On satelite right now 92L looks like a depression.
It's pretty much done, path will keep it an open wave and bring some rain to the islands. It'll be watched for a while, but I still can't see it developing into anything. My usual approach of finding reasons it won't develop and then eliminating them one by one until it has a decent chance, not the other way around. Climatology (It's June!) and the shear nw of the system were two things I couldn't ignore the last few days, and it's still the main driver of why I think it won't ever amount to anything.
The importance of the various factors change over the course of the season, but early and late season climatology is really far up there as a negative development factor. (Not so much between July-October)
| JoshuaK |
| (Weather Guru) |
| Thu Jun 17 2010 11:54 AM |
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Re: Central Atlantic Wave Being Watched
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What precisley would be the future forecast track? Would it most likely cross Cen. America into the E.Pac. or head NW into the Gulf, say about a week down the road? By then it might only be a typical wave, but I know from past experiences that something that flares up once may very well flare up again.
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danielw
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| (Moderator) |
| Thu Jun 17 2010 12:32 PM |
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Re: Central Atlantic Wave Being Watched
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Not very likely as the upper levels of the system are being sheared to the east. Sat loop below indicates the remaining low level remnants are still moving west toward the Lesser Antilles. The mountainous regions there shoud eliminate the possiblity of of anything crossing the C ATL gap.
http://cimss.ssec.wisc.edu/tropic2/real-...0000&loop=0
Further investigation reveals a rather large circulation that may just narrowly miss the Northern Lesser Antilles. Question is, will it pass thru the eastern Hebert Box .
Cyclonic circular pattern is located N of the dark spot E of the Islands and W of the thunderstorm complex.
| Ed in Va |
| (Weather Master) |
| Thu Jun 17 2010 07:30 PM |
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Re: Central Atlantic Wave Being Watched
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Still on life support, but not completely out the of picture, either, as there are still periodic flare-ups
http://www.ssd.noaa.gov/goes/east/carb/flash-wv.html
| hogrunr |
| (Weather Guru) |
| Thu Jun 17 2010 08:29 PM |
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Re: Central Atlantic Wave Being Watched
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It seems as though the shear is actually feeding moisture into the system right now. You can see from the WV imagery that it is bordered by very dry air to the north. For it to have a chance of doing anything, it needs to get out of the shear it is currently under (30-50 knots). It needs to make it past 70W.
11pm CST Edit: The convection is much stronger as to be expected overnight. Also to note though, the shear that was present over the system has begun a slight shift to the north. The system is now under approx. 20-30 knot shear instead of the previous range of up to 50 knots. It will be interesting to see what data can be gathered from the islands and nearby buoy's as this passes by.
There is a gap in all of the Satellite data, so it is hard to tell what the movement of the system is right now, but it seems to be West to WNW. The NHC has the system listed as having a 20% chance of development in the next 48 hours, still not much, but higher than the 0% they had it listed as in the previous reports.
CIMSS Shear Map
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danielw
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| (Moderator) |
| Fri Jun 18 2010 04:32 AM |
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Re: Central Atlantic Wave Being Watched
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Remnants of 92L continue to flare tonight. Moderate convection with about 40% coverage of lightning.
Upper cirrus cloud are starting to show thin 'fingers' suggestive of little to no shear at the upper levels on the western half of the system.
Martinique Radar is showing some level 4 thunderstorm activity but I don't see any circulation. Movement is toward the west.
http://www.meteo.fr/temps/domtom/antilles/pack-public/animation/animMOSAIC2.html
Java water vapor loop is here:
http://www.ssd.noaa.gov/goes/east/carb/loop-wv.html
92L has been removed from the www.ssd.noaa.gov page at this time.
| saltysenior |
| (Verified CFHC User) |
| Fri Jun 18 2010 10:32 PM |
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links
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hope i am doing this right........lost all old stuff on my ''bookmarks''.......could someone start a new thread with the best links for the coming hurricane season ??? one i can't find is a satellite view of africa showing the start of these waves.......thanks guys and i pray for a quite season w/ this oil floating around..
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danielw
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| (Moderator) |
| Fri Jun 18 2010 11:07 PM |
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links and 92L
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Most of the better satellite websites can be found on the Main Page. Just scroll down a bit.
92L is still going...
While shear has done some damage to the system is appears to be staying together as an area of thunderstorms. They haven't consolidated like they did yesterday/ last night. But it's a bit early in the evening in the Antilles.
We will have to wait and see what they system does over night as the mountains of the Antilles and the shear are trying to tear it apart.
Also you can try Dundee you will need to register, but its free. Also
http://www.ssd.noaa.gov/PS/TROP/trop-atl.html
| Old Sailor |
| (Storm Tracker) |
| Sat Jun 19 2010 01:58 AM |
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Re: links and 92L
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Well another year, if this was late July or August, 92invest would be on it's way to a be Hurricane,
This maybe a interesting year with higher temperatures then been recorded in recent history.
| berrywr |
| (Weather Analyst) |
| Sat Jun 19 2010 07:18 AM |
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Re: links and 92L
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I wouldn't write this tropical wave off yet. I've been looking at the GFS run this evening and there are a couple of interesting features; one being the mid-continental subtropical upper ridge setting up shop over the Mid-South and a piece of the Bermuda sub-tropical upper ridge off the coast of FL with an inverted upper trough near FL sandwiched between the two ridges aloft. Wind Shear in this entire area is quite light. It's something to keep an eye on as we go forward in time. The upper pattern isn't expected to change very much for several days and in fact the GFS at H+120 hours has a vorticity max in the Eastern Gulf of Mexico.
| berrywr |
| (Weather Analyst) |
| Sat Jun 19 2010 07:30 AM |
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Re: Central Atlantic Wave Being Watched
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Tropical Waves generally are shallow systems therefore steered by wind currents at & below 5000 feet or 850 milibars. You can see this by viewing upper level analysis and satellite imagery loops as low level features may in fact be going in completely opposite directions than for example the tops of thunderstorms. In satellite imagery posted within this thread you will note a very strong thunderstorm in the classic cell shape and some very, very cold tops; however you will note on the western edge how sharp it goes from very cold tops to non-existent in short order and quite a bit of blow off and debris to its east. Upper level winds are quite strong from the west literally shearing the system. The wave while capable of developing thunderstorms cannot remain cohesive from surface to the upper levels thus the wave is not in an environment for development into a depression at this time. As I posted a moment ago...if the wave continues to hold itself together there may be an opportunity beyond 72 to 96 hours as upper ridges aloft will be centered over the Mid-South and off the coast of FL with upper level troughing sandwiched between the two. For the moment wind shear is at a minimum over the entire area. Assuming the upper level trough remains weak; by weak not generating upper level wind shear an opportunity will exists as it steers itself from the hostile envelope it's currently in as of 19/00Z. I hope this helps?
| MichaelA |
| (Weather Analyst) |
| Sat Jun 19 2010 01:08 PM |
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Re: Central Atlantic Wave Being Watched
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It has been rather persistent in spite of the shear. Still bears watching as it continues to move toward Cuba, Bahamas, Florida.
Update: Lots of shear apparent in the latest vis pics.
| JoshuaK |
| (Weather Guru) |
| Sun Jun 20 2010 02:24 AM |
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Re: Central Atlantic Wave Being Watched
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Some of the latest Infrared Imagery shows a blob of convection firing up around what may be a (albiet weak) circulation center of some kind, can't tell if it's either H/M/L, but as of 01:45 UTC satellite shot it seemed to be centered at about 16.8N and 66.8W. Still a lot of shear going on though. But it's still kicking.
| Doombot! |
| (Weather Guru) |
| Sun Jun 20 2010 05:17 AM |
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Re: Central Atlantic Wave Being Watched
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Noticed the same thing to the SW of PR. Lets see how it fairs overnight.
| Storm Hunter |
| (Veteran Storm Chaser) |
| Sun Jun 20 2010 08:42 PM |
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Re: Central Atlantic Wave Being Watched
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I think that CMC and NOGAPS are on to something in the central carib. firing up next week... Upper level winds looks to be more favorable for tropical development... although GFS is stil kinda quiet until a week plus down the road. NOGAPS to me has down pretty good so far this season, esp. in the east pacific...
http://moe.met.fsu.edu/tcgengifs/ngp/2010062012/slp21.png