Disturbance East of Bahamas

[Ivanhater]

Well, the models are showing some sort of development with the wave behind the Antilles wave. Something to watch for sure...

It is the wave between the Antilles wave and 99L



Euro 72 hours


GFDL 126 hours..near Florida



18z NAM 84 hours

[Ivanhater]

[MiamiensisWx]

The low level vorticity at 850 mb is very weak in the vicinity of the convection. The main vorticity lobe is situated farther south, and it has been weakening. There is a high amplitude low level moisture surge in the area, but convergence is essentially non-existent. All of the convection is attributable to the well defined divergence (varying wind speeds among heights) in the area. Without substantial convergence/LL vorticity, this system will not have an opportunity for development. The projected favorable environment, represented by a well defined 250 mb anticyclone, also indicates the absence of any defined forcing for convection. The ECMWF and GFS do not develop a closed low/sfc reflection as the system passes through the Lesser Antilles. Only the unreliable NAM develops a sfc low. Thus, I don't envision any significant development with this system. Furthermore, any land interaction with Puerto Rico/Hispaniola would affect any remnant vorticity lobes.

[tolakram]

Glad you started this thread, because I noticed this:

http://www.ssd.noaa.gov/PS/TROP/TCFP/

[cycloneye]

Ivan,its getting dark in that visible loop.An infared image is needed.

[Gustywind]

[KWT]

Well the models are seeing something but really I can't see anything there to develop really to be honest, sure there is some convection but its got a massive way to go yet!

Still this seems to be the season where you take anything you can!

[Aric Dunn]

yeah keep an eye on it for sure.. I have been waiting for convection to fire with it as it approaches the islands.. all this system needs is some convergence and the surface and with the increasing moisture and upper divergence we may see some decent convection fire tonight. Given that there is a broad circulation that exists already, only a good increase in convection would give this system a shot as well.

[Ivanhater]

00z NAM really likes it

[cycloneye]

Yeah,it has in 66 hours a L over me.

[tailgater]

Pretty clear where the low level curvature in this pic.
http://cimss.ssec.wisc.edu/tropic2/real ... /wg8ir.GIF

[RL3AO]

TROPICAL WEATHER OUTLOOK
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
200 AM EDT TUE AUG 11 2009

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

A BROAD AREA OF LOW PRESSURE LOCATED A COUPLE HUNDRED MILES WEST
OF THE SOUTHERN CAPE VERDE ISLANDS IS MOVING WESTWARD AT 10 TO 15
MPH. THE ASSOCIATED SHOWER AND THUNDERSTORM ACTIVITY HAS INCREASED
SOMEWHAT AND THIS SYSTEM HAS THE POTENTIAL TO BECOME A TROPICAL
DEPRESSION DURING THE NEXT DAY OR SO. THERE IS A MEDIUM CHANCE...
30 TO 50 PERCENT...OF THIS SYSTEM BECOMING A TROPICAL CYCLONE
DURING THE NEXT 48 HOURS.

A TROPICAL WAVE LOCATED ABOUT 600 MILES EAST OF THE LESSER ANTILLES
IS PRODUCING DISORGANIZED SHOWERS AND THUNDERSTORMS. ANY
DEVELOPMENT OF THIS SYSTEM IS LIKELY TO BE SLOW AS IT MOVES
WESTWARD AT 10 TO 15 MPH. THERE IS A LOW CHANCE...LESS THAN 30
PERCENT...OF THIS SYSTEM BECOMING A TROPICAL CYCLONE DURING THE
NEXT 48 HOURS.

A SMALL AREA OF LOW PRESSURE ASSOCIATED WITH A TROPICAL WAVE IS
PRODUCING DISORGANIZED SHOWERS AND THUNDERSTORMS NEAR THE WINDWARD
ISLANDS. DEVELOPMENT OF THIS SYSTEM...IF ANY...IS EXPECTED TO BE
SLOW TO OCCUR AS IT MOVES WESTWARD AT 10 TO 15 MPH OVER THE
SOUTHEASTERN CARIBBEAN SEA DURING THE NEXT COUPLE OF DAYS. THERE
IS A LOW CHANCE...LESS THAN 30 PERCENT...OF THIS SYSTEM BECOMING A
TROPICAL CYCLONE DURING THE NEXT 48 HOURS.

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

$$
FORECASTER PASCH

[Fego]

[floridasun78]

yes it on map at 2am more circle on map

[Aric Dunn]

Ok peeps watch this much more closely today.. i can see a tightening circulation and convection firing on top of it now. this has the set up to develop pretty quickly..

[ronjon]

00Z GFDL actually develops this system at the end of the run for 99L (now TD No. 2) in the FL straits.

http://moe.met.fsu.edu/cgi-bin/gfdltc2.cgi?time=2009081100-invest99l&field=Sea+Level+Pressure&hour=Animation

[cycloneye]

ABNT20 KNHC 111136
TWOAT
TROPICAL WEATHER OUTLOOK
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
800 AM EDT TUE AUG 11 2009

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

THE NATIONAL HURRICANE CENTER HAS INITIATED ADVISORIES ON TROPICAL
DEPRESSION ONE...LOCATED ABOUT 280 MILES WEST OF THE SOUTHERNMOST
CAPE VERDE ISLANDS.


SHOWER AND THUNDERSTORM ACTIVITY ASSOCIATED WITH A TROPICAL WAVE
LOCATED ABOUT 600 MILES EAST OF THE LESSER ANTILLES REMAINS
DISORGANIZED. DEVELOPMENT OF THIS SYSTEM IS LIKELY TO BE SLOW AS
IT MOVES WESTWARD AT 10 TO 15 MPH. THERE IS A LOW CHANCE...LESS
THAN 30 PERCENT...OF THIS SYSTEM BECOMING A TROPICAL CYCLONE DURING
THE NEXT 48 HOURS.

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

PUBLIC ADVISORIES ON TROPICAL DEPRESSION ONE ARE ISSUED UNDER WMO
HEADER WTNT32 KNHC AND UNDER AWIPS HEADER MIATCPAT2. FORECAST/
ADVISORIES ON TROPICAL DEPRESSION ONE ARE ISSUED UNDER WMO HEADER
WTNT22 KNHC AND UNDER AWIPS HEADER MIATCMAT2.

$$
FORECASTER BERG

[Gustywind]

000
AXNT20 KNHC 111152
TWDAT

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
805 AM EDT TUE AUG 11 2009

TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL
AMERICA...GULF OF MEXICO...CARIBBEAN SEA...NORTHERN SECTIONS
OF SOUTH AMERICA...AND ATLANTIC OCEAN TO THE AFRICAN COAST
FROM THE EQUATOR TO 32N. THE FOLLOWING INFORMATION IS BASED
ON SATELLITE IMAGERY...METEOROLOGICAL ANALYSIS...WEATHER
OBSERVATIONS...AND RADAR.

BASED ON 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
WWWW UTC.

...TROPICAL WAVES...

TROPICAL WAVE IS ALONG 49W/50W S OF 18N MOVING W NEAR 10 KT. THE
AXIS OF THE WAVE IS ORIENTED WITHIN A BROAD MOISTURE MAXIMUM
OBSERVED IN TOTAL PRECIPITABLE WATER IMAGERY WITH CLUSTERS OF
SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE WITHIN 75/90
NM OF LINE FROM 18N48W TO 13N52W.
$$
WALLACE

[Gustywind]

Here is a sat/pic of this twave:

[wx247]

Thunderstorm activity doesn't appear to be concentrated. I will keep one eye on this for changes, but it looks like for now there are some other areas with better potential.