Caribbean disturbance 94L dumping heavy rains on Jamaica

By: Dr. Jeff Masters , 4:44 PM GMT on June 05, 2011

Share this Blog
8
+

A large, wet, and disorganized tropical disturbance (Invest 94L) continues to spread heavy rain to the Central Caribbean near Jamaica. Rain has fallen continuously at Jamaica's Kingston Norman Manley Airport since midnight, with 1.89" having fallen from midnight to noon local time. Sustained winds of 24 mph also affected Kingston between 7am and 8am this morning. Satellite-estimated rainfall amounts of 1.4" per hour occurred in ocean regions 100 miles to the southeast of Kingston this morning, and heavy rains of up to 1/2" per hour are probably affecting portions of Jamaica early this afternoon, judging by the recent increase in heavy thunderstorm activity seen on visible satellite loops. This imagery also shows a slow increase in organization of 94L in recent hours, with spiral bands beginning to develop to the southeast of the center. There is a broad, poorly-defined circulation apparent that is not well enough defined to make 94L a tropical depression. Water vapor satellite loops show a region of dry air on the west side of 94L, and this dry air is interfering with the storm's organization. However, upper air balloon soundings from Kingston and the Cayman Islands taken at 8am EDT this morning show much moister air at mid levels of the atmosphere compared to Saturday (2% humidity at 500 mb on Saturday, compared to 49% this morning at Grand Cayman), and 94L appears to be gradually overcoming its dry air issues. Wind shear remains in the moderate range, 15 - 20 knots, and is predicted by the SHIPS model to remain below 20 knots through Tuesday morning. Water temperatures in the Central Caribbean are about 1°C above average, 28 - 28.5°C, which is 2°C above the threshold needed to support development of a tropical storm.


Figure 1. Rainfall rates of up to 1.4" per hour (pink colors) were estimated by the F-15 satellite for 94L at 6:02am EDT Jun 5, 2011.

Since 94L is so large and is battling dry air, it is taking its sweet time to develop, and today's mission by the Hurricane Hunters has been cancelled. A new mission is scheduled for Monday afternoon at 2pm EDT. This morning's 06Z model runs are pretty unimpressed with 94L, with most of them showing little or no development. At 2pm EDT on Sunday, NHC gave the disturbance a 40% of developing into a tropical depression by Tuesday. If 94L stays to the south, its chances of development are greater, since a band of very high wind shear of 30 - 50 knots lies over Cuba and the southern Bahama Islands. The disturbance is expected to meander slowly westward or northward over the next two days, with Jamaica and southeastern Cuba being the primary targets for very heavy rains of 4 - 8 inches through Tuesday. Haiti and Central Cuba can expect somewhat lesser rains of 3 - 6 inches. If 94L does develop into a tropical depression and moves northwards over Cuba by Wednesday, I don't see the storm attaining hurricane strength, due to the high wind shear. The primary threat from 94L will be very heavy rains, capable of causing life-threatening flash flooding.


Figure 2. Afternoon satellite image of the Central Caribbean disturbance 94L.

Jeff Masters

Reader Comments

Comments will take a few seconds to appear.

Post Your Comments

Please sign in to post comments.

or Join

Not only will you be able to leave comments on this blog, but you'll also have the ability to upload and share your photos in our Wunder Photos section.

Display: 0, 50, 100, 200 Sort: Newest First - Order Posted

Viewing: 147 - 97

Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 | 35 | 36 | 37 | 38 | 39Blog Index

Quoting MiamiHurricanes09:
Post removed. Had to notify WunderBlog Admin.




i find it odd that he did not all so give you a 24hr ban for that vary lucky that he did not do that
Member Since: Posts: Comments:
Quoting kmanislander:


Good afternoon

I agree. It is starting to take on that comma shape that is a clear indication of a well defined and tightening circulation. In addition there are some very high cold cloud tops near the area of lowest pressure and that will help to drive surface pressures down some more.

And it has all happened VERY quickly.
Surprised me, I have to admit.
Member Since: Posts: Comments:
144. JRRP
?
Member Since: Posts: Comments:
143. IKE

Quoting clwstmchasr:


I'm looking at the visible loop and it appears that I am seeing some rotation. Are my eyes playing tricks on me or are you seeing the same thing?
Center...that I see looks near 16.8N and 79W...
Member Since: June 9, 2005 Posts: 23 Comments: 37860
Quoting Hurricanes101:
AL, 94, 2011060518, , BEST, 0, 168N, 796W, 25, 1007, DB

Movement just west of due north, judging by data from Tropical Atlantic.
Member Since: Posts: Comments:
141. IKE

Quoting nrtiwlnvragn:
Located 0.4N, 0.2W from previous


AL 94 2011060512 BEST 0 164N 794W 25 1007 DB
AL 94 2011060518 BEST 0 168N 796W 25 1007 DB
Uh--moving WNW too.
Member Since: June 9, 2005 Posts: 23 Comments: 37860
Quoting AllStar17:
Convection continuing to fire to the south of Jamaica. Certainly looks like it is trying to wrap it around to me.


It's organising more quickly than I thought it would even a few hours ago when the convection 'ball' started to wane. Looks like it's wrapping itself around. Still no very tight circulation though.
Member Since: Posts: Comments:
Quoting nrtiwlnvragn:
Located 0.4N, 0.2W from previous


AL 94 2011060512 BEST 0 164N 794W 25 1007 DB
AL 94 2011060518 BEST 0 168N 796W 25 1007 DB


NW drift
Member Since: August 19, 2006 Posts: 0 Comments: 15948
Evolution of 94L..impressive improvement





Member Since: Posts: Comments:
Post removed. Had to notify WunderBlog Admin.
Member Since: Posts: Comments:
Quoting IKE:
94L looks like it's getting it's act together.


Good afternoon

I agree. It is starting to take on that comma shape that is a clear indication of a well defined and tightening circulation. In addition there are some very high cold cloud tops near the area of lowest pressure and that will help to drive surface pressures down some more.
Member Since: August 19, 2006 Posts: 0 Comments: 15948
Located 0.4N, 0.2W from previous


AL 94 2011060512 BEST 0 164N 794W 25 1007 DB
AL 94 2011060518 BEST 0 168N 796W 25 1007 DB
Member Since: September 23, 2005 Posts: 15 Comments: 11342
132. IKE
Looking at 94L....NHC...it deserves a recon mission now. Looks better. I see the COC and convection is near it.
Member Since: June 9, 2005 Posts: 23 Comments: 37860
I just e-mailed Miami. He just said that report post 112 until it's removed.
Member Since: Posts: Comments:
Looks like they removed Comment 112.
Member Since: Posts: Comments:
hey guys I think the LLC is right under the MLC which will put it at 16.8N 76.8W moving W-WNW very very slowly
Member Since: June 13, 2009 Posts: 2 Comments: 12716
128. 7544
Quoting sammywammybamy:


Convection now directly above both COC's (LLC and MLC)






things are changing fast game on now for 94l looking much better in gthe last 6 hours could it bring so fla some rain tho or past it by thats the big question ?
Member Since: Posts: Comments:
man that's a shame, had to iggy MH09. Good catch, ya'll.

Bet recon is wishing they'da kept the evening flight. They just might find a TD come tomorrow.
Member Since: Posts: Comments:
Convection continuing to fire to the south of Jamaica. Certainly looks like it is trying to wrap it around to me.
Member Since: Posts: Comments:
Quoting stormwatcherCI:
TROPICAL WEATHER OUTLOOK
NWS NATIONAL HURRICANE CENTER MIAMI FL
200 PM EDT SUN JUN 5 2011

FOR THE NORTH ATLANTIC...CARIBBEAN SEA AND THE GULF OF MEXICO...

1. THUNDERSTORM ACTIVITY HAS BECOME A LITTLE BETTER ORGANIZED IN
ASSOCIATION WITH A BROAD LOW PRESSURE SYSTEM LOCATED ABOUT 150
MILES SOUTHWEST OF JAMAICA. ALTHOUGH SURFACE PRESSURES ARE ONLY
SLOWLY DECREASING...SOME GRADUAL DEVELOPMENT OF THIS LARGE
DISTURBANCE IS POSSIBLE OVER THE NEXT COUPLE OF DAYS AS WINDS IN
THE MIDDLE LEVELS OF THE ATMOSPHERE BRIEFLY BECOME SOMEWHAT
FAVORABLE. THERE IS A MEDIUM CHANCE...40 PERCENT...OF THIS SYSTEM
BECOMING A TROPICAL CYCLONE DURING THE NEXT 48 HOURS. AN AIR FORCE
RESERVE RECONNAISSANCE AIRCRAFT IS SCHEDULED TO INVESTIGATE THE LOW
PRESSURE AREA MONDAY AFTERNOON...IF NECESSARY. REGARDLESS OF
DEVELOPMENT...HEAVY RAINS COULD CAUSE FLASH FLOODS AND MUD SLIDES
OVER PORTIONS OF HAITI AND JAMAICA AS THE SYSTEM MOVES SLOWLY
TOWARD THE NORTHWEST OR NORTH OVER THE NEXT FEW DAYS.

ELSEWHERE...TROPICAL CYCLONE FORMATION IS NOT EXPECTED DURING THE
NEXT 48 HOURS.

$$
FORECASTER STEWART
NNNN


Not surprised there. I doubt they cancel tomorrow's flight.
Member Since: Posts: Comments:
AL, 94, 2011060518, , BEST, 0, 168N, 796W, 25, 1007, DB
Member Since: Posts: Comments:
123. IKE
94L looks like it's getting it's act together.
Member Since: June 9, 2005 Posts: 23 Comments: 37860
122. IKE
Post 112 is missing up the blog. Add him temporarily to ignore list.
Member Since: June 9, 2005 Posts: 23 Comments: 37860
Either the blog is taking a break, or those using Inept Explorer are having a problem with post #112.
You can temporarly "ignore user" if it is true.
Member Since: September 23, 2005 Posts: 15 Comments: 11342
TROPICAL WEATHER OUTLOOK
NWS NATIONAL HURRICANE CENTER MIAMI FL
200 PM EDT SUN JUN 5 2011

FOR THE NORTH ATLANTIC...CARIBBEAN SEA AND THE GULF OF MEXICO...

1. THUNDERSTORM ACTIVITY HAS BECOME A LITTLE BETTER ORGANIZED IN
ASSOCIATION WITH A BROAD LOW PRESSURE SYSTEM LOCATED ABOUT 150
MILES SOUTHWEST OF JAMAICA. ALTHOUGH SURFACE PRESSURES ARE ONLY
SLOWLY DECREASING...SOME GRADUAL DEVELOPMENT OF THIS LARGE
DISTURBANCE IS POSSIBLE OVER THE NEXT COUPLE OF DAYS AS WINDS IN
THE MIDDLE LEVELS OF THE ATMOSPHERE BRIEFLY BECOME SOMEWHAT
FAVORABLE. THERE IS A MEDIUM CHANCE...40 PERCENT...OF THIS SYSTEM
BECOMING A TROPICAL CYCLONE DURING THE NEXT 48 HOURS. AN AIR FORCE
RESERVE RECONNAISSANCE AIRCRAFT IS SCHEDULED TO INVESTIGATE THE LOW
PRESSURE AREA MONDAY AFTERNOON...IF NECESSARY. REGARDLESS OF
DEVELOPMENT...HEAVY RAINS COULD CAUSE FLASH FLOODS AND MUD SLIDES
OVER PORTIONS OF HAITI AND JAMAICA AS THE SYSTEM MOVES SLOWLY
TOWARD THE NORTHWEST OR NORTH OVER THE NEXT FEW DAYS.

ELSEWHERE...TROPICAL CYCLONE FORMATION IS NOT EXPECTED DURING THE
NEXT 48 HOURS.

$$
FORECASTER STEWART
NNNN
Member Since: October 9, 2008 Posts: 0 Comments: 8436
wow between doc and the nhc we know about nothing......i guess this one just has everyone stumped....bit surprised they didnt send in the hunter
Member Since: Posts: Comments:
Looking for the Discussion now...
Member Since: Posts: Comments:
06/05/2011 01:34 PM EDT


000
ABNT20 KNHC 051734
TWOAT

TROPICAL WEATHER OUTLOOK
NWS NATIONAL HURRICANE CENTER MIAMI FL
200 PM EDT SUN JUN 5 2011

FOR THE NORTH ATLANTIC...CARIBBEAN SEA AND THE GULF OF MEXICO...

THUNDERSTORM ACTIVITY HAS BECOME A LITTLE BETTER ORGANIZED IN
ASSOCIATION WITH A BROAD LOW PRESSURE SYSTEM LOCATED ABOUT 150
MILES SOUTHWEST OF JAMAICA. ALTHOUGH SURFACE PRESSURES ARE ONLY
SLOWLY DECREASING...SOME GRADUAL DEVELOPMENT OF THIS LARGE
DISTURBANCE IS POSSIBLE OVER THE NEXT COUPLE OF DAYS AS WINDS IN
THE MIDDLE LEVELS OF THE ATMOSPHERE BRIEFLY BECOME SOMEWHAT
FAVORABLE. THERE IS A MEDIUM CHANCE...40 PERCENT...OF THIS SYSTEM
BECOMING A TROPICAL CYCLONE DURING THE NEXT 48 HOURS. AN AIR FORCE
RESERVE RECONNAISSANCE AIRCRAFT IS SCHEDULED TO INVESTIGATE THE LOW
PRESSURE AREA MONDAY AFTERNOON...IF NECESSARY. REGARDLESS OF
DEVELOPMENT...HEAVY RAINS COULD CAUSE FLASH FLOODS AND MUD SLIDES
OVER PORTIONS OF HAITI AND JAMAICA AS THE SYSTEM MOVES SLOWLY
TOWARD THE NORTHWEST OR NORTH OVER THE NEXT FEW DAYS.

ELSEWHERE...TROPICAL CYCLONE FORMATION IS NOT EXPECTED DURING THE
NEXT 48 HOURS.

$$
FORECASTER STEWART
Member Since: Posts: Comments:
Quoting CybrTeddy:
Red alert in the EPAC, 40% for 94L.

First red alert of the EPAC season! C'mon 94L, you can do it too!
Member Since: Posts: Comments:
..
Member Since: Posts: Comments:
Quoting Hurricanes101:


MOST of the people who say these things are the ones we know not to trust; relax

the majority of the blog has and will continue to keep a level head about this


Key word being "most."
Member Since: Posts: Comments:
Quoting Seflhurricane:
94L has not even formed yet and we have people saying there will be watches for florida , this is how people get cranked up on here , there is not even alot of model support so we dont know where it will end up.


um humm!
Member Since: Posts: Comments:
Quoting Seflhurricane:
94L has not even formed yet and we have people saying there will be watches for florida , this is how people get cranked up on here , there is not even alot of model support so we dont know where it will end up.


MOST of the people who say these things are the ones we know not to trust; relax

the majority of the blog has and will continue to keep a level head about this
Member Since: Posts: Comments:
Latest as a cat from ~10:30 this morning eastern time








Link
Member Since: September 23, 2005 Posts: 15 Comments: 11342
Nooooo way (&#Wd%)

Member Since: August 23, 2008 Posts: 0 Comments: 1918
One thing that can be said is that no one knows where this thing is going or how intense it will be.
Member Since: Posts: Comments:
Red alert in the EPAC, 40% for 94L.
Member Since: Posts: Comments:
94L has not even formed yet and we have people saying there will be watches for florida , this is how people get cranked up on here , there is not even alot of model support so we dont know where it will end up.
Member Since: Posts: Comments:
Quoting KEEPEROFTHEGATE:
you are doing it again
Dont shoot the messanger!
Member Since: Posts: Comments:
Quoting Seflhurricane:
who are the locals??? what news stations because there are some like channel 7 who exagerate things alot


You can always count on the local weathermen to be doomcasters...
Member Since: Posts: Comments:
Quoting BahaHurican:
I'm thinking 60 - 65 mph are about outer limits, especially if it stays west rather than coming due north. Your 45 does sound more like the realm of possibility, though. Frankly, it doesn't have to even get to named system status to satisfy me - IF we get a couple of inches of rain with it....
As I've always said..The name don't mean a thang as long as it comes with heavy rain.Pretty awesome.
Member Since: Posts: Comments:
Quoting RukusBoondocks:
local just said watches and warnings could be issued for west FL next week
you are doing it again
Member Since: Posts: Comments:

Viewing: 147 - 97

Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 | 35 | 36 | 37 | 38 | 39Blog Index

Top of Page

About

Jeff co-founded the Weather Underground in 1995 while working on his Ph.D. He flew with the NOAA Hurricane Hunters from 1986-1990.

Local Weather

Overcast
28 °F
Overcast

JeffMasters's Recent Photos

Lake Effort Snow Shower Over Windsor, Ontario
Sunset on Dunham Lake
Pictured Rocks Sunset
Sunset on Lake Huron