MikeC
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| (Admin) |
| Sun Jun 05 2011 12:30 PM |
Low Near Jamaica Likely to Hang Around a While
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7AM EDT 7 June 2011 Update
The system near Jamaica (94L) is being heavily impacted by windshear today, and chances for development are dropping quickly, although parts of the system main remain, it appears that very little if any rain from this system will occur in Florida. The trough coming out it may be enough to break the overall dry pattern for later.
The rest of the Atlantic is fairly quiet too.
7AM EDT 6 June 2011 Update
The disturbance near Jamaica (94L) is a little less organized this morning, it's very difficult to find a low level circulation (or even if one still exists), and it may have moved west of the deep convection, and there is no sign of anything trying to reform closer to where the activity is.
Likely this means it will hold it's status today at around 30-50% chance for development, models are extremely spread out in where this system may eventually go, but it seems that if the low level circulation moves westward it will be less likely to do much.
Pressures in the area have been falling though, which is an indicator that it won't go away anytime soon.
Recon is scheduled to go out this afternoon, and if it does there may be a much better idea of what is going on around it. It's too early to tell if there will be any rain from this in the US (Jamaica and Hispaniola will continue to see the rains from it until it moves off)
5PM EDT 5 June 2011 Update
The area in the Caribbean, 94L, has a higher chance to develop than before, around 40%, but still is not certain, the area is very broad today and there is still no real signs of the low level circulation getting much convection wise. If it manages to get both good outflow and convection over the low level circulation, then chances start to go up for development.
No recon went out today after all, but one is scheduled for tomorrow. Models are all over the place, one trend is that if the storm strengthens (especially quickly) it tends to favor more westward direction, if it does not develop it will stay more easterly. Odds still slightly favor it not developing, and remaining weak.
For direction, and travel, until a system develops, the models tend to to be very inaccurate.
Original Update
The area of low pressure, southwest of Jamaica (known as 94L) has managed to persist through some of the worst conditions for development recently, and now is actually in a position that does allow some development. Convection in the area is on the increase this morning, and if it persists will slowly raise chances for development. Right now the National Hurricane Center gives it a 30% shot to develop within the next 2 days. What is going against it is a lack of convection on the western side of the area, which is keeping it from organizing all that much.
Movement is going to be very difficult to call as there is no organized center of circulation, models are split, but the possibility of it moving back westward have gone up, but this depends on how long the system hangs out in the Caribbean, which could be days, or even most of the week. If it does move more westward, the chances of it running into higher shear are greater, and thus would keep it weak.
Although recon was scheduled the last two days, all flights were cancelled. However for today, conditions seem well enough that the recon aircraft may actually go out. With data from that we may have a better idea what is going on there.
Just to the north of the system is a strong stream of dry air, but the system is remaining south of that, which may allow it to drift a bit further west. Although the highest likelihood is that it remains east and out, the chance of it moving back toward the Yucatan are slowly going up, but it will be a long wait to determine it.
Most of the time systems in June do not do all that much, the general conditions are not quite set up for it, but the possibility remains since it likely to remain pretty much where it is this week. Which means it must be watched through .
{{StormCarib}}
{{StormLinks|94L|94|2|2011|2|94L}}
| doug |
| (Weather Analyst) |
| Sun Jun 05 2011 12:49 PM |
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Re: Low Near Jamaica Likely to Hang Around a While
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Looks to be a developing system. There are signs of a developing ridge to the west and the system is on the eastern periphery of that. The pattern to the north is breaking down. Would not be surprised by some westward movement and intensification.
| chase 22 |
| (Weather Hobbyist) |
| Sun Jun 05 2011 01:08 PM |
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Re: Low Near Jamaica Likely to Hang Around a While
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I agree with Doug. It looks much more impressive now than it did a couple of days ago. If it does move West however, wouldn't it run into some pretty decent shear?
| Hugh |
| (Senior Storm Chaser) |
| Sun Jun 05 2011 03:26 PM |
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Re: Low Near Jamaica Likely to Hang Around a While
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It does look more impressive than at one point, but it still is discombobulated.
There's an obvious LLC, but the convection is displaced from it. They've pulled the trigger at times
in these situations, and at other times, not pulled it. In any case, I don't see much rapid development unless
the environment drastically improves. Still, it's the most likely to develop invest we've had this season so far.
| okihabu |
| (Verified CFHC User) |
| Sun Jun 05 2011 03:46 PM |
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Re: Low Near Jamaica Likely to Hang Around a While
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I aint no expert like you folks, but that Low sitting up by Ms, Ls have a effect on where this Invest will go?
| Hugh |
| (Senior Storm Chaser) |
| Sun Jun 05 2011 03:48 PM |
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Re: Low Near Jamaica Likely to Hang Around a While
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Quote:
I aint no expert like you folks, but that Low sitting up by Ms, Ls have a effect on where this Invest will go?
Only marginally, I think. It's too far away and too weak.
| MichaelA |
| (Weather Analyst) |
| Sun Jun 05 2011 05:00 PM |
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Re: Low Near Jamaica Likely to Hang Around a While
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It's satellite presentation is better today and it seems to be getting more vertically stacked. If this structure persists, I wouldn't be surprised to see a TD declared either late today or early tomorrow. The models are still inconclusive, though.
| Edski |
| (Verified CFHC User) |
| Sun Jun 05 2011 06:25 PM |
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Re: Low Near Jamaica Likely to Hang Around a While
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NHC has it up to a 40% chance now. IR loop seems to show an outflow feature over SE Cuba. Looks better to my untrained eyes than it did 3 hours ago.
| Hugh |
| (Senior Storm Chaser) |
| Sun Jun 05 2011 07:18 PM |
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Re: Low Near Jamaica Likely to Hang Around a While
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It looks like a TD. Yet NHC cancelled today's recon flight, so it won't be a TD today.
| weathernet |
| (Storm Tracker) |
| Sun Jun 05 2011 08:07 PM |
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Re: Low Near Jamaica Likely to Hang Around a While
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Though the tops have significantly cooled this afternoon, i'd have to say it appears that 94L has made significant strides during the day. Looks to possibly be forming a LLC around 17N & 78W ( though one might make an argument for rotation a couple degrees east of that point). NHC indicated a general westward motion, which I think is the first time this system seems to have had enough consolidation to determine motion. Sure enough, looking at the loop this afternoon, it would appear a slow westward motion may be underway.
| WesnWylie |
| (Weather Guru) |
| Sun Jun 05 2011 08:20 PM |
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Re: Low Near Jamaica Likely to Hang Around a While
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Looking at the recent satellite loop here: http://weather.cod.edu/satrad/index.php, it looks like 94L could be winding up this afternoon. I definitely see the circulation developing. With shear forecast to remain about the same or even weaken some more, I think we could see a Tropical Depression develop fairly soon. There does not appear to be much dry air across the region to hinder organization over the next couple days. It will be interesting to see what the NHC puts 94L's chances at later today.
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MikeC
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| (Admin) |
| Sun Jun 05 2011 09:12 PM |
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Re: Low Near Jamaica Likely to Hang Around a While
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I still don't think we'll see much from this system, other than rain. There are plenty of places in Florida and along the Gulf that need the rain, so a weak tropical system would be beneficial.
| MichaelA |
| (Weather Analyst) |
| Sun Jun 05 2011 10:43 PM |
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Re: Low Near Jamaica Likely to Hang Around a While
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Rain without damaging winds would be great for Florida right now. 94L still is looking fairly well organized this afternoon. If this organization persists, I still believe that a TD will be declared, at least sometime tomorrow. Some of the models are beginning to indicate a system moving into the eastern Gulf of Mexico, but the HWRF has been really consistent in moving it to the NE into the Atlantic. Of course, the models will remain inconsistent from run to run until there is a definite center to initialize on.
| MichaelA |
| (Weather Analyst) |
| Mon Jun 06 2011 02:53 PM |
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Re: Low Near Jamaica Likely to Hang Around a While
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94L certainly looks much more disorganized today than it did yesterday. Not much of a LL center south of Grand Cayman, and there seems to be a mid-level vortex near 15N; 79W. The 0600 GFDL still develops a strong TD/weak TS and moves it into the eastern GoM on Friday/Saturday while the NGP moves a weak to moderate low across Florida. The GFS dissipates the system pretty much in place and the HWRF still moves a system NE into the Atlantic. The CMC splits between the NGP and the HWRF models. As it appears this morning, I'm beginning to believe the GFS is closer to being correct.
| scottsvb |
| (Weather Master) |
| Mon Jun 06 2011 04:45 PM |
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Re: Low Near Jamaica Likely to Hang Around a While
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I don't know.. I think the system looks better now than 24hrs ago.
Finally the midlevels have moisture to work with. We see T-Storms
firing SW of the center of the circulation which now looks alittle
tighter than before,but still broad. Pressure has come down
slightly to 1007mb.. also recently T-Storms are just north of
the center near 18.1N and 82W... movement is slowly NW.
This needs to continue to increase its T-Storms around the COC
this evening and tonight.. if it does.. it wont take much to make this
a TD.. Ciruclation is well definded.. we just need T-Storms near
the center. Windshear will increase later on Tues-Thurs as it
approaches western Cuba.. so if this does develop.. it better
tonight.
| weathernet |
| (Storm Tracker) |
| Mon Jun 06 2011 04:54 PM |
Re: Low Near Jamaica Likely to Hang Around a While
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Yep, guess I'd have to "second" Michael's prior post, on both accounts. 94L has pretty much appeared to have wound down from yesterday, and at least to me appears to be a lazy broad eddy within a generally larger monsoonal low. Looking at "back to back" GFS runs, it would appear that 94L may simply continue to drift westward with the low level flow, and simply cease to exist as an invest. Looking at this morning's 200mb -350mb winds, I see upper air conditions appearing to deteriorate in less than 48 hours. In what oddly would appear to be strengthening "El Nino" like sub tropical westerlies, very little "real estate" throughout the tropics would appear to look all too conducive for any significant development over the near term. Worse part is that we here in S. Florida ( not unlike many other areas as well ), may not even benefit from much of the moisture of 94L.
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danielw
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| (Moderator) |
| Mon Jun 06 2011 05:46 PM |
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Re: Low Near Jamaica Likely to Hang Around a While
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I saw a comment from a Tropical MET over the last few days referring to 94L as a " Sit and Spin LOW". Seems to be right on the mark.
Current surface CoC at 1731Z or 1:30 PM EDT is near... 18N/ 82W. Mid level center seems to be co-located to the east of the surface CoC.
http://www.ghcc.msfc.nasa.gov/GOES/goeseastconus.html
(X=298 Y=389)
| MichaelA |
| (Weather Analyst) |
| Mon Jun 06 2011 06:12 PM |
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Re: Low Near Jamaica Likely to Hang Around a While
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2 PM TWO ups it to 50%. I wonder what NHC is seeing that I'm not.
| Bloodstar |
| (Moderator) |
| Mon Jun 06 2011 06:19 PM |
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Re: Low Near Jamaica Likely to Hang Around a While
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If I were to hazard a guess, I'd say it's because of the increasing convection around the center of the low along with a moistening of the atmosphere at the mid level heights.
It's a big sloppy mess, but the ingredients are there for something to form.
| scottsvb |
| (Weather Master) |
| Mon Jun 06 2011 06:20 PM |
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Re: Low Near Jamaica Likely to Hang Around a While
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Quote:
Yep, guess I'd have to "second" Michael's prior post, on both accounts. 94L has pretty much appeared to have wound down from yesterday, and at least to me appears to be a lazy broad eddy within a generally larger monsoonal low. Looking at "back to back" GFS runs, it would appear that 94L may simply continue to drift westward with the low level flow, and simply cease to exist as an invest. Looking at this morning's 200mb -350mb winds, I see upper air conditions appearing to deteriorate in less than 48 hours. In what oddly would appear to be strengthening "El Nino" like sub tropical westerlies, very little "real estate" throughout the tropics would appear to look all too conducive for any significant development over the near term. Worse part is that we here in S. Florida ( not unlike many other areas as well ), may not even benefit from much of the moisture of 94L.
Actually as you can see the NHC said what I said 1 hour later.. .probably cause I know some of the staff there?
Anyways.. yesterday it wasnt as good as today. It was far away from the convection and yesterday you were seeing the midlevel swirl.
Tropical systems are all about the convection near a LLC.
| doug |
| (Weather Analyst) |
| Mon Jun 06 2011 07:12 PM |
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Re: Low Near Jamaica Likely to Hang Around a While
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The "cleanser" will be that ULL in the SW GOM which is shoving everything eastward. I think 50% is very generous, based on current vivible evidence, and a general NE'wd movement of the low level moisture.
| MichaelA |
| (Weather Analyst) |
| Mon Jun 06 2011 07:36 PM |
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Re: Low Near Jamaica Likely to Hang Around a While
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I'm still unimpressed looking at the latest sat pics. 91E looks much better over on the Pacific side.
| scottsvb |
| (Weather Master) |
| Mon Jun 06 2011 08:55 PM |
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Re: Low Near Jamaica Likely to Hang Around a While
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91E will become a hurricane though.. 70% chance of that.. 50-50 on the WC thing
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Ed Dunham
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| (Former Meteorologist & CFHC Forum Moderator (Ed Passed Away on May 14, 2017)) |
| Mon Jun 06 2011 08:55 PM |
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Re: Low Near Jamaica Likely to Hang Around a While
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Invest 94L still has a long way to go before it can be considered as a tropical cyclone. Since the 18Z development probability upgrade to 50 percent, the convection has been on the wane again. Very early this morning three separate low to mid-level circulations were evident within the larger envelope of cyclonic turning. Convective outflow boundary collisions have altered the convective pattern throughout the day with some areas on the decrease while other areas were developing - but the total pattern really hasn't changed all that much.
One correction: Pressure has actually remained steady today - at 1140Z the central pressure was estimated at 1006MB and at 1837Z it was still 1006MB.
ED
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MikeC
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| (Admin) |
| Mon Jun 06 2011 10:56 PM |
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Re: Low Near Jamaica Likely to Hang Around a While
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Shear is starting to set in on the disturbance, and it I'm thinking the recon won't go out tomorrow. I'd be surprised at this point if it does develop.
| scottsvb |
| (Weather Master) |
| Tue Jun 07 2011 02:45 AM |
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Re: Low Near Jamaica Likely to Hang Around a While
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Yeah... key for this was tonight.. and it's lost the convection it had from the series of weak midlevel lows near and to its west today. I give this now a 20% chance of coming back.. but probably wont be till it gets in the GOM by Thurs-Friday.. but 20% isnt much of a chance.
| weathernet |
| (Storm Tracker) |
| Tue Jun 07 2011 05:49 AM |
Re: Low Near Jamaica Likely to Hang Around a While
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Well, as most of us have posted, 94L clearly has lacked and continues to lack certain dynamics necessary for further development. Had the deep layer motion existed a couple days ago, so to allow the system to move ENE or NE, then the "net" shear would have been less impacting and perhaps a depression or weak storm might have formed under less formidable upper air conditions. In the face of the increasing sub tropical jet, it would just seem unrealistic to expect that any amount of consolidation might be adequite in building such an upper anticyclone that such long latitude westerlies would be rendered insignificant.
As far as Florida's parched lawns are concerned, we have certainly seen our share of unorganized training of deep Caribbean moisture over the years. On past occassions, over 48 hours of copious precipitation has meant widespread areas receiving 3-6 inches ( or more ) of rain. I hope i'm wrong, but am fearing that most of the low level moisture from 94L will simply pass to the south of most areas, while limited impact of increase in moisture, be mostly limited to a thickening Cirrus deck and perhaps very widely scattered light to moderate showers. Low level convergence will then play some role in what regions might receive some appreciable precip, but i'd not anticipate 2 or more inches over Lake "O" or other widespread areas of South/Central Florida. On the topic of "drought busting rains" ( mod's feel free to relocate this to a more appropriate forum ), I recall years ago how I much enjoyed speaking with Jim Lushine with Miami NWS and recall his unofficial correlation between unusually dry South Florida months of May and heightened risk of tropical cyclone landfalls for the region. Though no concrete relationship was established, I would be curious to know how continued dry conditions into June might have shown further correlation to those years with S. Florida landfalls.
(The 7AM Update did include commentary on the drought, however any 'correlation' questions should be directed to the Hurricane Ask/Tell Forum.)
| MichaelA |
| (Weather Analyst) |
| Tue Jun 07 2011 01:53 PM |
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Re: Low Near Jamaica Likely to Hang Around a While
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It looks like the moisture is going to miss Florida as it's being carried off to the NE and E. That t-storm cluster south of Puerto Rico and the Virgin Islands looks rather suspicious to me today.
| adam s |
| (Verified CFHC User) |
| Tue Jun 07 2011 07:53 PM |
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Re: Low Near Jamaica Likely to Hang Around a While
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What are the chances that the moisture with Invest 94L affects Florida? Do you think Invest 94L has already lost it's time to become a tropical depression?
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MikeC
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| (Admin) |
| Tue Jun 07 2011 08:14 PM |
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Re: Low Near Jamaica Likely to Hang Around a While
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The chances of it becoming a depression were never very good, but it's basically lost that. It also appears the system will not really add any rainfall to Florida, unfortunately. If system stays there a bit longer, what the "NAM" model shows is more of the moisture stream heading north, which increases chances, but not as much as needed.