000
AXNT20 KNHC 051800
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL  
205 PM EDT SUN SEP 05 2010

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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1745 UTC. 

...SPECIAL FEATURES...

A 1009 MB LOW...REMNANT OF GASTON...IS ABOUT 600 NM E OF THE 
LESSER ANTILLES NEAR 17N51W MOVING W NEAR 10 KT. SATELLITE 
IMAGERY INDICATES A LOW LEVEL SWIRL WITH SMALL CLUSTERS OF 
SCATTERED MODERATE/ISOLATED STRONG CONVECTION TO THE W FROM 
15N-19N BETWEEN 50W-54W. ALTHOUGH ACTIVITY IS CURRENTLY 
LIMITED...ENVIRONMENTAL CONDITIONS APPEAR CONDUCIVE FOR 
DEVELOPMENT OF THIS SYSTEM AND A TROPICAL DEPRESSION COULD 
RE-FORM DURING THE NEXT DAY OR TWO. THERE IS A HIGH CHANCE OF 
THIS SYSTEM BECOMING A TROPICAL CYCLONE AGAIN DURING THE NEXT 48 
HOURS.

A BROAD AREA OF LOW PRESSURE COVERS THE SW GULF WHERE A SURFACE 
TROUGH IS ANALYZED FROM A 1005 MB LOW 35 NM NE OFF THE COAST OF 
THE CITY OF VERACRUZ NEAR 19.6N 95.4W. THE SURFACE TROUGH 
EXTENDS NNE ALONG 23N95W TO 26N93W. SCATTERED SHOWERS/ISOLATED 
THUNDERSTORMS COVER THE AREA S OF 27N W OF 91W TO INLAND OVER 
MEXICO. OFFICIAL DATA FROM SEVERAL WEATHER STATIONS IN THE 
VICINITY OF THE CITY OF VERACRUZ HAVE REGISTERED BETWEEN 1 AND 2 
INCHES OF RAIN IN THE PAST 24 HRS. SHORT RANGE COMPUTER MODELS 
SUGGEST THIS SYSTEM WILL CONTINUE TO MOVE NNW OVER THE NEXT 
COUPLE OF DAYS WITH SCATTERED MODERATE TO STRONG 
CONVECTION...BEGINNING TO AFFECT THE TEXAS COAST BY TUESDAY 
MORNING. ENVIRONMENTAL CONDITIONS APPEAR FAVORABLE FOR 
ADDITIONAL DEVELOPMENT AND A TROPICAL DEPRESSION COULD FORM 
DURING THE NEXT DAY OR SO BEFORE THE SYSTEM MOVES INLAND. THERE 
IS A HIGH CHANCE OF THIS SYSTEM BECOMING A TROPICAL CYCLONE 
DURING THE NEXT 48 HOURS

...TROPICAL WAVES...

TROPICAL WAVE REMAINS INLAND OVER WEST AFRICA ALONG 10W MOVING W 
NEAR 10 KT. SATELLITE IMAGERY INDICATES CYCLONIC FLOW NEAR THE 
WAVE AXIS CONCENTRATED NEAR A 1009 MB LOW ALONG AND THE AXIS 
NEAR 9N. THIS SYSTEM IS EXPECTED TO ENTER THE ATLC OVER THE NEXT 
24 HRS.

...ITCZ...

A MONSOONAL TROUGH EXTENDS FROM THE COASTAL WATERS OF W AFRICA 
NEAR 19N20W ALONG 10N23W TO 6N35W...WHERE THE ITCZ AXIS BEGINS 
AND CONTINUES WESTWARD ALONG 10N45W TO 12N60W. SCATTERED 
MODERATE TO STRONG CONVECTION IS E OF THE TROUGH FROM 6N TO 14N 
BETWEEN THE COAST OF WEST AFRICA AND 22W. CLUSTERS OF SIMILAR 
CONVECTION ARE FROM 4N TO 8N BETWEEN 30W-43W. 

...DISCUSSION...

GULF OF MEXICO...
THE PRIMARY FOCUS THIS AFTERNOON FOR THE GULF OF MEXICO IS THE 
SURFACE TROUGH/LOW IN THE SPECIAL FEATURES ABOVE. A LONGWAVE 
UPPER LEVEL TROUGH COVERING MOST OF THE S AND SE CONUS ENTERS 
THE N GULF NOTED BY STRONG SUBSIDENCE ON WATER VAPOR IMAGERY. 
THIS UPPER LEVEL FEATURE SUPPORTS A RATHER WEAK STATIONARY FRONT 
THAT EXTENDS FROM THE W ATLC ACROSS THE NORTHERN FLORIDA 
PENINSULA INTO THE NE GULF NEAR 29N83W CONTINUING WESTWARD TO 
29N92W. A SURFACE TROUGH IS ANALYZED WITHIN 30 N MI S OF THE 
STATIONARY FRONT BETWEEN 83W AND 91W. THIS SCENARIO IS ENHANCING 
SCATTERED MODERATE TO ISOLATED STRONG CONVECTION N OF 26N E OF 
92W. 

CARIBBEAN SEA...
BROAD ELONGATED UPPER LEVEL LOW CENTERED N OF PUERTO RICO 
SUPPORTS A SURFACE TROUGH ANALYZED ALONG 24N64W 20N65W 16N64W 
ENHANCING SCATTERED WEAK TO MODERATE CONVECTION TO THE EASTERN 
CARIBBEAN N OF 12N E OF 70W. A SURFACE TROUGH IS TO THE SW OF 
THE UPPER TROUGH EXTENDING FROM NORTHERN COLOMBIA NEAR 10N74W TO 
THE N COAST OF NICARAGUA NEAR 14N83W GENERATING SCATTERED 
SHOWERS AND ISOLATED THUNDERSTORMS WITHIN 100 N MI ON EITHER 
SIDE OF THE TROUGH. COMPUTER MODELS SUGGEST THIS AREA OF 
CONVECTION WILL LINGER IN THE SW CARIBBEAN OVER THE NEXT 24 HRS. 
RELATIVELY DRY/STABLE CONDITIONS IS NOTED ELSEWHERE ACROSS THE 
CARIBBEAN THIS AFTERNOON. 

ATLANTIC OCEAN...
BROAD ELONGATED UPPER LEVEL LOW CENTERED N OF PUERTO RICO NEAR 
20N66W SUPPORTS A SURFACE TROUGH ANALYZED ALONG 24N64W 20N65W 
16N64W ENHANCING SCATTERED WEAK TO MODERATE CONVECTION S OF 25N 
BETWEEN 64W AND 72W. UPPER LEVEL JET STREAK/TROUGH MOVING NE OFF 
THE EASTERN SEABOARD IS ENHANCING SCATTERED MODERATE CONVECTION 
N OF 27N BETWEEN 68W AND 75W. ELSEWHERE ACROSS THE ACROSS THE 
DISCUSSION AREA...BROAD MID/UPPER LEVEL SUB-TROPICAL RIDGE 
DOMINATES THE ATLC AND SUPPORTS THE SURFACE 1024 MB HIGH NEAR 
36N45W. 

FOR ADDITIONAL INFORMATION PLEASE VISIT
HTTP://WWW.HURRICANES.GOV/MARINE

$$

GARCIA