Wave/Surface Trough in Central Caribbean

[Gustywind]

Hey Rock, are you referencing the area just approaching the southern islands? Nice little convection blowup this afternoon.

This area is a twave, twave number 21 given the Pro Mets of Meteo-France Martinica. Thus, this twave is expected to bring numerous showers sometimes strong tonight, and that's why they decided to put Martinica in yellow alert for a risk of strong showers and tstorms begining tonight till tommorow morning.
http://www.meteo.gp/EspacePro/donnees/b ... ilance.php
The yellow pic is Martinica under an yellow alert ( french version).

[cycloneye]

This is the 8 PM discussion about Tropical Wave/Surface Trough/Low Pressure.

A CARIBBEAN SEA TROPICAL WAVE IS ALONG 63W TO THE SOUTH OF 20N
19N54W 14N56W 10N56W MOVING WESTWARD ABOUT 20 KNOTS. RAINSHOWERS
ARE POSSIBLE FROM 12N TO 20N BETWEEN 60W AND 64W. THE TROPICAL
WAVE IS MOVING TOWARD THE AREA OF MIDDLE LEVEL TO UPPER LEVEL
CYCLONIC WIND FLOW WITH A TROUGH THAT HAS BEEN IN THE CARIBBEAN
SEA FOR THE LAST FEW DAYS.

BROAD SURFACE LOW PRESSURE...POSSIBLY WITH A DEVELOPING SURFACE
TROUGH...COVERS THE ATLANTIC OCEAN IMMEDIATELY TO THE EAST OF
THE EASTERN CARIBBEAN SEA ISLANDS...FROM 9N TO 16N BETWEEN 52W
AND 60W. CONVECTIVE PRECIPITATION...SCATTERED STRONG FROM 12N TO
14N BETWEEN 58W AND 60W...APPROACHING BARBADOS. BROKEN TO
OVERCAST MULTILAYERED CLOUDS AND POSSIBLE PRECIPITATION COVER
THE REST OF THE AREA FROM 7N TO 16N BETWEEN 51W AND 58W.

AN ATLANTIC OCEAN SURFACE TROUGH IS ALONG 47W/48W FROM 8N TO
16N...MOVING WESTWARD ABOUT 10 KNOTS. A 1012 MB LOW PRESSURE
CENTER IS ALONG THE TROUGH NEAR 14N. BROKEN TO OVERCAST
MULTILAYERED CLOUDS AND POSSIBLE PRECIPITATION COVER THE
ATLANTIC OCEAN FROM 9N TO 16N BETWEEN 44W AND 51W.

[tailgater]

Barbados has had at the very least a sharp wave pass or a small LLC.

24 Hour Summary
Time
EDT (UTC) Temperature
F (C) Dew Point
F (C) Pressure
Inches (hPa) Wind
MPH Weather
Latest 1 AM (5) Aug 07 78 (26) 78 (26) 29.88 (1012) S 9 showers in the vicinity
Midnight (4) Aug 07 78 (26) 78 (26) 29.88 (1012) SSW 8
11 PM (3) Aug 06 78 (26) 78 (26) 29.88 (1012) SW 12
10 PM (2) Aug 06 77 (25) 77 (25) 29.88 (1012) S 14 light rain
9 PM (1) Aug 06 78 (26) 78 (26) 29.88 (1012) ESE 8 light rain
8 PM (0) Aug 06 77 (25) 77 (25) 29.85 (1011) ESE 10 light rain; showers in the vicinity
7 PM (23) Aug 06 78 (26) 77 (25) 29.85 (1011) NNE 7
6 PM (22) Aug 06 78 (26) 77 (25) 29.85 (1011) ENE 3
5 PM (21) Aug 06 78 (26) 75 (24) 29.85 (1011) E 6 light rain
4 PM (20) No Data
3 PM (19) Aug 06 84 (29) 75 (24) 29.85 (1011) ESE 13
2 PM (18) Aug 06 80 (27) 78 (26) 29.88 (1012) E 14

[cycloneye]

TROPICAL WEATHER OUTLOOK
NWS NATIONAL HURRICANE CENTER MIAMI FL
800 AM EDT WED AUG 7 2013

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

CLOUDINESS AND SHOWERS ASSOCIATED WITH A WEAK AREA OF LOW PRESSURE
ARE MOVING WESTWARD ACROSS THE WINDWARD ISLANDS AND THE EASTERN
CARIBBEAN SEA. ENVIRONMENTAL CONDITIONS ARE FORECAST TO BE
UNFAVORABLE FOR DEVELOPMENT OVER THE NEXT SEVERAL DAYS. THIS SYSTEM
HAS A LOW CHANCE...NEAR 0 PERCENT...OF BECOMING A TROPICAL CYCLONE
DURING THE NEXT 48 HOURS...AND A LOW CHANCE...NEAR 0 PERCENT...
DURING THE NEXT 5 DAYS.

&&

FIVE-DAY FORMATION PROBABILITIES ARE EXPERIMENTAL IN 2013. COMMENTS
ON THE EXPERIMENTAL FORECASTS CAN BE PROVIDED AT...

http://WWW.NWS.NOAA.GOV/SURVEY/NWS-SURVEY.PHP?CODE=ETWO

$$
FORECASTER AVILA

[ninel conde]

i have been reading where it might have a shot if it can make it to the west carib.

[abajan]

TROPICAL WEATHER OUTLOOK
NWS NATIONAL HURRICANE CENTER MIAMI FL
800 AM EDT WED AUG 7 2013

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

CLOUDINESS AND SHOWERS ASSOCIATED WITH A WEAK AREA OF LOW PRESSURE
ARE MOVING WESTWARD ACROSS THE WINDWARD ISLANDS AND THE EASTERN
CARIBBEAN SEA. ENVIRONMENTAL CONDITIONS ARE FORECAST TO BE
UNFAVORABLE FOR DEVELOPMENT OVER THE NEXT SEVERAL DAYS. THIS SYSTEM
HAS A LOW CHANCE...[b]NEAR 0 PERCENT...OF BECOMING A TROPICAL CYCLONE
DURING THE NEXT 48 HOURS...AND A LOW CHANCE...NEAR 0 PERCENT...
DURING THE NEXT 5 DAYS.

&&

FIVE-DAY FORMATION PROBABILITIES ARE EXPERIMENTAL IN 2013. COMMENTS
ON THE EXPERIMENTAL FORECASTS CAN BE PROVIDED AT...

http://WWW.NWS.NOAA.GOV/SURVEY/NWS-SURVEY.PHP?CODE=ETWO

$$
FORECASTER AVILA
[/b]

So far, the 48 hour and 5 day outlooks have always been matching. Kinda strange to me.

[Gustywind]

8AM TWD.


A SURFACE TROUGH ASSOCIATED WITH A 1011 MB LOW NEAR 13N60W IS
GENERATING A CLUSTER OF MODERATE CONVECTION AND TSTMS OVER THE
LESSER ANTILLES FROM 12N-15N BETWEEN 60W-63W. THE VIRGIN ISLANDS
REPORTED RAINSHOWERS WITHIN THE LAST HOUR ASSOCIATED WITH THE
PASSAGE OF THIS WAVE.

[RL3AO]

So far, the 48 hour and 5 day outlooks have always been matching. Kinda strange to me.

Well here is the current EPAC TWO to show how it works.

A BROAD AREA OF LOW PRESSURE IS FORECAST TO FORM ABOUT 1000 TO 1500
MILES SOUTHWEST OF THE SOUTHERN TIP OF THE BAJA CALIFORNIA
PENINSULA OVER THE WEEKEND...WHEN CONDITIONS APPEAR TO BE FAVORABLE
FOR SOME DEVELOPMENT. THIS SYSTEM HAS A LOW CHANCE...NEAR 0
PERCENT...OF BECOMING A TROPICAL CYCLONE DURING THE NEXT 48
HOURS...AND A MEDIUM CHANCE...30 PERCENT...OF BECOMING A TROPICAL
CYCLONE DURING THE NEXT 5 DAYS.

[Gustywind]

Given the latest weather forecast edited from the Pro Mets of Meteo-France Martinica, the southern tip of the island have been showered. Values between 20 to 40 millimeters in 12 hours have been recorded in numerous localities ( St Esprit, Ducos, Lamentin, Rivière Salée and les Trois Ilets.

Link related to the latest weather forecast for Martinica. See below.

http://www.meteo.fr/temps/domtom/antill ... ivi_ma.pdf (French version)

[wxman57]

So far, the 48 hour and 5 day outlooks have always been matching. Kinda strange to me.

That tends to happen when there are no disturbances with a chance of developing in the tropics, or when the only chance of development is within the first 48 hrs.

As for this disturbance, it's going to be battling strong wind shear east of a retrograding upper-level low/trof over the next 5 days. That will probably mean it will retain some squalls, but development chances are very low. Best chance for development will be when it crosses into the East Pac early next week.

Since most East Pac storms develop from waves that cross from the Caribbean, I wonder if the NHC will mention it in the East Pac 5-day outlook?

[ROCK]

this is going to get confusing when you throw in 48hr chances then 5 day chances......why couldnt they leave well enough alone?

[abajan]

@RL3AO & wxman57
Thx for that info. Certainly clarifies things.

@ROCK
I'm inclined to agree but I guess we'll see how it goes.

[floridasun78]

when wx post bad news for tropical wave he look like want have few storm system season wx what your forecast for 2013 season???

[Sanibel]

Looks like another Dorian however things can change quickly at this time even with shear.

[ROCK]

the frist LLC has passed the islands and now has some popcorn showers forming close to the LLC.....the second LLC feature behind it has not reached the islands and has limited convection....still though it has a nice LLC....

http://weather.msfc.nasa.gov/GOES/goeseasthurr.html

[Dean4Storms]

Dry air and shear, may need to watch it come western Carib.

[Hurricaneman]

Dry air and shear, may need to watch it come western Carib.

The GFS does send this as a weak low to the Florida Panhandle around day 9 so it cant be completely discounted but we'll see if it continues with development into pre truncation in coming runs

[Dean4Storms]

Ugh, anyone else seeing the convection popping near the LLC and also the banding in the NE Quad???


http://www.ssd.noaa.gov/goes/east/carb/flash-vis.html

[ROCK]

Ugh, anyone else seeing the convection popping near the LLC and also the banding in the NE Quad???


http://www.ssd.noaa.gov/goes/east/carb/flash-vis.html

I see it Dean...fighting some shear though...


here is a 4KM sat view..Ramm has a floater on it

http://rammb.cira.colostate.edu/ramsdis ... opical.asp

[wxman57]

I don't see any evidence of an LLC (Low-Level Circulation center). I do see that the wave is about to reach an area of quite high wind shear associated with an upper-level low to its east (eastern Bahamas).