Caribbean disturbance 94L dumping heavy rains on Jamaica

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

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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

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... New record high temperature set at Galveston...

... The record high for the month of June has been tied...


A record high temperature of 99 degrees was set at Galveston today.
This breaks the old record of 92 degrees set in 1875... 136 years ago.

This also ties the 99 degree record high temperature for the month
of June... which was set on June 18th in 1918... 93 years ago.
Member Since: Posts: Comments:
Quoting kmanislander:


Okay. I see it and so do others. You see something different. It's oaky to dosagree, nicely.
i see the LLC but it is very broad and not well defined its moving to the wnw
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Very interesting circulation developing south of Jamaica looking at microwave

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Quoting kmanislander:
Hi there Drak. Long time no see. Studying hard eh LOL



Hey Kman! It's been a while.I have been studying hard, but I still
have not taken any meteorology major required core courses. I will be
starting them in the fall. Right now i'm taking summer classes at FSU,
by choice.
Member Since: Posts: Comments:
Christchurch area again


Magnitude
5.0
Date-Time
Sunday, June 05, 2011 at 21:09:55 UTC
Monday, June 06, 2011 at 09:09:55 AM at epicenter
Time of Earthquake in other Time Zones
Location
43.570°S, 172.391°E
Depth
3.8 km (2.4 miles) (poorly constrained)
Region
SOUTH ISLAND OF NEW ZEALAND
Distances
22 km (13 miles) W of Christchurch, New Zealand
212 km (131 miles) SSE of Westport, New Zealand
296 km (183 miles) NNE of Dunedin, New Zealand
320 km (198 miles) SW of WELLINGTON, New Zealand
Location Uncertainty
horizontal +/- 4.5 km (2.8 miles); depth +/- 4.9 km (3.0 miles)
Parameters
NST= 74, Nph= 77, Dmin=18.9 km, Rmss=1.35 sec, Gp= 58°,
M-type=body wave magnitude (Mb), Version=5




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94L will get 40% again, maximum of 50%. This system is far too large to have spun up into something near a tropical depression in six hours.
Member Since: August 10, 2010 Posts: 2 Comments: 1971
Quoting wunderkidcayman:

I don't see no LLC where you ploted Kman looked at VIS and RGB close up zoomed out and even covering the MLC with paper don't see it


Okay. I see it and so do others. You see something different. It's okay to disagree, nicely.
Member Since: August 19, 2006 Posts: 0 Comments: 15816
ent
conditions in
Kingston / Norman Manley 77 °F
Mostly cloudy. Warm.
Change to Celsius
Change Units
Description: Mostly cloudy. Warm.
Temperature: 77 °F Comfort Level: 79 °F
Wind: 12 mph from 100° East
Last update: Sun 5:00 PM EST
Member Since: Posts: Comments:

Quoting kmanislander:
Hi there Drak. Long time no see. Studying hard eh LOL

Hey Kman! It's been a while.I have been studying hard, but I still have not taken any meteorology major required core courses. I will be starting them in the fall. Right now i'm taking summer classes at FSU, by choice.

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Lots of good info here:

Hazard Mapping System Fire and Smoke Product
Member Since: September 21, 2010 Posts: 1 Comments: 3690
"boing".......


your # 107
Member Since: July 3, 2005 Posts: 424 Comments: 128259
Quoting kmanislander:


16.8 N and 80.2 W

Motion to the W very slowly, maybe 8 mph my best guess. 4 hours would give you 80.7 West

I don't see no LLC where you ploted Kman looked at VIS and RGB close up zoomed out and even covering the MLC with paper don't see it
Member Since: June 13, 2009 Posts: 2 Comments: 11975
933. txjac
AtHome ...it's way to hot here! Got to be 106 where I am at in Houston!
Member Since: April 24, 2010 Posts: 1 Comments: 2514
Quoting Mrsenseofhumor:


What does this button do?


Didn't do nuttin, Hit it about a dozen times. The one on the right works though. :)
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Quoting kmanislander:


16.8 N and 80.2 W

Motion to the W very slowly, maybe 8 mph my best guess. 4 hours would give you 80.7 West

Thanks for that.
Member Since: October 24, 2005 Posts: 0 Comments: 24307
Quoting wunderkidcayman:
the LLC will relocate to where the MLC is (plus I don't think there is such thing as a Upper Level Circulation in this system at all there is an upper level anticyclone) and I do not see LLC at the location that some of you guys are yapping about tonight we'll have a COC relocation and an increase in convection there as well. Done, that is it. no more about this


Wow. Take a break man. I just had a nice snooze and came back all relaxed with a great fuzzy feeling. Don't gives us a bad name on the blog my man. It's okay to have an opinion, so just wait and see if you are right.
Member Since: August 19, 2006 Posts: 0 Comments: 15816
Quoting pottery:

Yes, SIR !!
LOL


Lol. Just was fixin to say that. :)
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Quoting CybrTeddy:


I say its staying at 40%.
94L isn't organizing rapidly anytime soon.
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Quoting Levi32:


Regarding wind shear, the EPAC has less than the Atlantic in the early and late season, but can have more than the Atlantic in the height of the season due to the upper easterlies that come from the monsoonal circulation over Mexico. These easterly upper winds are usually said to reduce wind shear, but that's in the Atlantic where the surface winds are predominantly easterly as well. In the eastern Pacific during the height of the season, the surface winds are predominantly southwesterly or nearly calm farther north, which results in stronger vertical wind shear, since the upper winds are in the opposing direction.

As to why there is a SW flow in the EPAC but not the Atlantic, it is due to the monsoon trough. This is a heat-induced trough which develops over central America during the summer due to solar heating which lowers the surface pressure. Wind rushes out of the southwest from the ocean towards this low pressure, meeting the northeast trades from the Caribbean, thus forming the monsoon trough.

The Atlantic does not have a landmass like central America, so much of the MDR consists of a regular ITCZ with SE trades meeting NE trades. However, there is a monsoon trough near and west of Africa, due to the African monsoonal circulation. Again, summer heating reduces the surface air pressure over Africa, drawing southwesterly winds off of the tropical Atlantic. You can see this on summer ASCAT passes.


do you have any links to good meteorology/weather learning websites?


I'd like to learn all the stuff you have!
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Someone was asking about the smoke over Colorado. Found this article on BBC News:

Fire crews are battling to contain a massive blaze in Arizona that is threatening mountain communities in the east of the state.

The fire, covering 225 sq miles (583 sq km) is being described as the third largest in the state's history.

Smoke from the burning pine forests can be seen in neighbouring New Mexico and Colorado.

Arizona Governor Jan Brewer, who flew over the fire, described the rapidly moving blaze as a "frightening sight".

The fire was expected to grow, given a forecast for winds and lightning.

Most residents of the resort town of Greer, in the White Mountains, left on Saturday, packing their belongings in to vehicles as what is being called the "Wallow Fire" moved closer.

On Sunday, the town was shrouded in smoke.
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Quoting wunderkidcayman:
the LLC will relocate to where the MLC is (plus I don't think there is such thing as a Upper Level Circulation in this system at all there is an upper level anticyclone) and I do not see LLC at the location that some of you guys are yapping about tonight we'll have a COC relocation and an increase in convection there as well. Done, that is it. no more about this

Yes, SIR !!
LOL
Member Since: October 24, 2005 Posts: 0 Comments: 24307
..yapping?

94L Multiplatform Satellite Surface Wind Analysis 1800 UTC
Member Since: July 3, 2005 Posts: 424 Comments: 128259
I see no reason for the NHC to increase the formation probability at this time, as convection has waned and not become any better organized since this morning. Further organization may occur tonight, but right now it should stay at 40% at 8pm.
Member Since: November 24, 2005 Posts: 635 Comments: 26647
Quoting pottery:
KMan, where do you put the LLC right now, and can you say where you think it will be in say 4 hrs?


16.8 N and 80.2 W

Motion to the W very slowly, maybe 8 mph my best guess. 4 hours would give you 80.7 West
Member Since: August 19, 2006 Posts: 0 Comments: 15816
Quoting xcool:
i say 50%


I say 40%.
Member Since: Posts: Comments:
the LLC will relocate to where the MLC is (plus I don't think there is such thing as a Upper Level Circulation in this system at all there is an upper level anticyclone) and I do not see LLC at the location that some of you guys are yapping about tonight we'll have a COC relocation and an increase in convection there as well. Done, that is it. no more about this
Member Since: June 13, 2009 Posts: 2 Comments: 11975
916. xcool
i say 50%
Member Since: September 26, 2009 Posts: 2 Comments: 15670
Quoting tropicfreak:
875. PcolaDan 10:56 PM GMT on June 05, 2011 This comment has been removed for violating the Community Standards


LOL, I miss those times when comments were marked that way, that way I couldn't see the troll's comments, nowadays I have to.


Wait, what did I miss? I didn't have one pulled, did I? I still see me at 875. I'm confused (as opposed to my normal oblivious state).
There are still quite a few marked that way, at times.
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Fire near Buna is mostly contained, no damage... Link


Jasper County fire near Beech Grove now fully contained...

Link

Kountze fire now contained, evacuees return home...
Link


Another fire sparks off near Kountze Sunday

Link
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94L Floater - RGB Color Infrared Loop
Member Since: July 3, 2005 Posts: 424 Comments: 128259
Quoting Tazmanian:
94L could be up too 70% next two


I say its staying at 40%.
Member Since: July 8, 2005 Posts: 259 Comments: 24016
KMan, where do you put the LLC right now, and can you say where you think it will be in say 4 hrs?
Member Since: October 24, 2005 Posts: 0 Comments: 24307
Quoting Levi32:


You have the convective diurnal cycle correct. The pressure tides are driven by a wave in the upper atmosphere that follows the sun (the sun's position directly overhead). The highest amplitude cycle has a lowest pressure at 4am, which is also convective DMAX. The secondary period minimum at 4pm I believe is a secondary wave fluctuation in the upper atmosphere. Such a fluctuation will not necessarily control the instability of the atmosphere at that time of day, since the convective DMIN at that time is the dominant force.
thanks for your help.

And its clear that the diurinal pressure cycle is the dominant pressure over the diurinal pressure cycle caused by the convective diurinal cycle, as seen in the buoy charts you have been posting

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Quoting tropicfreak:


Besides tropical [thunder]storm Bonnie, but that was a typical rainy day in the sunshine state.


Businesses and life was running as usual during that storm. Even in Dade County where the storm made landfall, I've seen severe thunderstorms cause more Havok.
Member Since: Posts: Comments:
875. PcolaDan 10:56 PM GMT on June 05, 2011 This comment has been removed for violating the Community Standards


LOL, I miss those times when comments were marked that way, that way I couldn't see the troll's comments, nowadays I have to.
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We need an Aircraft out there.
Stormpetrol, dont you have a Plane?
Lets GO man>>>>>
Member Since: October 24, 2005 Posts: 0 Comments: 24307
Hi there Drak. Long time no see. Studying hard eh LOL
Member Since: August 19, 2006 Posts: 0 Comments: 15816
Quoting Mrsenseofhumor:


Sure Mr Fish Curtains plays most of them characters.
hahahahahahaha
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Happy HOT Sunday.

Current Location:
Clear
Vidor, TX
102.9 °F Clear
Nearby Airports
Orange | 99 °F | Clear
Beaumont | 97 °F | Haze
Beaumont / Port Arthur | 100 °F | Clear
Sabine Pass | This station is not reporting.


Nearby Weather Stations
Thomas Park | 102.9 °F
Beaumont | 100.9 °F
Central Gardens - AirLiquide | 97.8 °F
Allen Meadows Subdivision | 97.4 °F
Silsbee Meteorological Center | 106.3 °F
Burrell Cove | 95.6 °F


Record breaking heat today, any relief tomorrow?
By Bert Charan - bio | email


Sunday June 5, 2011

Records today in SE Texas/ W. La:

Beaumont 104 (Old record: 99- 1977)

Lake Charles 103 (Old record: 99- 1977)

Houston 105 (Old record: 99- 1977)

Galveston 99 (Old record: 99- 1977)

Lafayette, La. 100 (Old record: 99- 1977)

Alexandria, La. 101 (Old record: 99- 1977)

New Iberia, La. 101 (Old record: 99- 1977)

College Station, Tx. 100 (Old record: 99- 1977)

Record breaking temperatures today throughout the area. We hit a brand new record of 104 this Sunday, shattering the old record of 98 set back in 1977. Heat indices are between 105-108. Temps all across the area have hit or exceeded 100 degrees with dangerous heat indices.
Member Since: Posts: Comments:
Quoting 7544:
look at the spin just south of jamacia at 78 west could it relocate there
It will not "relocate;" it will continue wnw. We won't see any significant development until convection builds above the established llc
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Back for a while

I see that daytime heating finally took a toll of the convection but not as bad as yesterday. However, its only a couple of hours until the cool of the evening begins and another round of deep convection sets in.

Buoy 42057 is down to 1006.8 and pressure here on the Western end of the island a steady 1008.4.

Member Since: August 19, 2006 Posts: 0 Comments: 15816
94L could be up too 70% next two
Member Since: May 21, 2006 Posts: 5091 Comments: 115079

Quoting CyclonicVoyage:


Surely very broad and I agree with you. You think they may be triangulating the broad low to a mean center?? Hard to imagine they would do that but, I can see any other reason why they would place it in that location based on obs.

 Yes they do that sometimes until things become better defined. They can always relocate next cyclone.

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Quoting alfabob:

I'm seeing that as well, Alpha.
What a Nice Storm LOL, it's like an Exam!
Member Since: October 24, 2005 Posts: 0 Comments: 24307

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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.