000
AXNT20 KNHC 172359
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL  
805 PM EDT SAT SEP 17 2011

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...WEATHER OBSERVATIONS...RADAR...AND
METEOROLOGICAL ANALYSIS.

BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY
THROUGH 2315 UTC.

...SPECIAL FEATURES...
NONE.

...THE ITCZ/THE MONSOON TROUGH...

THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 20N16W TO 
A 1009 MB LOW NEAR 10N20W...TO A 1009 MB LOW NEAR 12N32W...TO A 
1009 MB LOW NEAR 10N37W...TO 9N43W. THE ITCZ CONTINUES FROM 
9N43W TO 8N54W TO 10N60W. SCATTERED MODERATE TO ISOLATED STRONG 
CONVECTION IS INLAND OVER WEST AFRICA FROM 8N-13N BETWEEN 
10W-15W. WIDELY SCATTERED MODERATE CONVECTION IS FROM 9N-13N 
BETWEEN 20W-28W. SCATTERED MODERATE CONVECTION IS FROM 7N-11N 
BETWEEN 33W-40W...AND FROM 13N-15N BETWEEN 34W-37W. 

...DISCUSSION...

THE GULF OF MEXICO...
THE TAIL END OF A DISSIPATING STATIONARY FRONT IS OVER N FLORIDA 
AND THE NE GULF OF MEXICO FROM 30N81W TO 28N87W. SCATTERED 
SHOWERS ARE WITHIN 30 NM OF THE FRONT. ELSEWHERE...SCATTERED 
MODERATE CONVECTION IS ALONG THE COAST OF S TEXAS FROM 27N-29N 
BETWEEN 96W-98W. SIMILAR CONVECTION IS INLAND OVER THE YUCATAN 
PENINSULA W OF 88W. MOSTLY FAIR WEATHER IS OVER THE REMAINDER OF 
THE GULF. EXPECT THE FRONT TO COMPLETELY DISSIPATE IN A FEW 
HOURS AND FOR SURFACE RIDGING TO DOMINATE FOR THE NEXT 24-48 
HOURS WITH E-SE FLOW AND MOSTLY FAIR WEATHER.   

THE CARIBBEAN SEA...
A SURFACE TROUGH IS OVER HONDURAS AND THE NW CARIBBEAN FROM 
13N87W TO 19N86W. ISOLATED MODERATE CONVECTION IS WITHIN 120 NM 
OF THE TROUGH. ANOTHER SURFACE TROUGH IS OVER THE E CARIBBEAN 
FROM 10N65W TO 18N64W. WIDELY SCATTERED MODERATE CONVECTION IS E 
OF THE TROUGH AXIS FROM 10N-20N BETWEEN 56W-63W. THE MONSOON 
TROUGH EXTENDS FROM N COLOMBIA TO COSTA RICA. SCATTERED MODERATE 
CONVECTION IS FROM 7N-16N BETWEEN 75W-84W. 10-20 KT TRADEWINDS 
ARE OVER THE CARIBBEAN WITH STRONGEST WINDS ALONG THE COAST OF N 
COLOMBIA. EXPECT THE SURFACE TROUGHS TO DRIFT W OVER THE NEXT 24 
HOURS WITH CONVECTION. ALSO EXPECT CONTINUED CONVECTION OVER THE 
SW CARIBBEAN DUE TO THE MONSOON TROUGH. 

THE ATLANTIC OCEAN...
A SURFACE TROUGH IS OVER THE W ATLANTIC FROM 30N70W TO 25N74W TO 
E CUBA AT 20N76W. SCATTERED MODERATE CONVECTION IS FROM 24N-28N 
BETWEEN 70W-77W TO INCLUDE PORTIONS OF THE CENTRAL BAHAMAS. A 
1021 MB HIGH IS OVER THE CENTRAL ATLANTIC NEAR 33N54W. A 
DISSIPATING COLD FRONT IS ALSO OVER THE CENTRAL ATLANTIC FROM 
31N34W TO 28N37W TO 28N40W. SCATTERED SHOWERS ARE WITHIN 120 NM 
OF THE FRONT. THE THREE SURFACE LOWS EMBEDDED ON THE MONSOON 
TROUGH ARE ENHANCING CONVECTION OVER THE TROPICS. EXPECT THESE 
LOWS TO MOVE W OVER THE NEXT 24 HOURS. ALSO EXPECT MORE 
CONVECTION E OF THE LESSER ANTILLES OVER THE NEXT 24 HOURS.  
 
FOR ADDITIONAL INFORMATION PLEASE VISIT
HTTP://WWW.HURRICANES.GOV/MARINE

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FORMOSA