000
AXNT20 KNHC 192353
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL  
805 PM EDT MON SEP 19 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...

A 1008 MB LOW IS NEAR 12N39W. SCATTERED MODERATE CONVECTION IS 
FROM 10N-14N BETWEEN 37W-41W. ENVIRONMENTAL CONDITIONS STILL 
APPEAR FAVORABLE FOR A TROPICAL DEPRESSION TO FORM DURING THE 
NEXT FEW DAYS. THE LOW CENTER IS FORECAST TO MOVE WESTWARD AT 
5-10 KT. 

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

THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 18N16W TO 
9N25W TO A 1008 MB LOW NEAR 12N39W TO 14N44W. THE MONSOON TROUGH 
HAS BECOME THE DOMINANT FEATURE ACROSS THE TROPICAL ATLC WITH NO 
INTER-TROPICAL CONVERGENCE ZONE. WIDELY SCATTERED MODERATE 
CONVECTION IS FROM 5N-10N BETWEEN 13W-28W. SCATTERED MODERATE TO 
STRONG CONVECTION IS FROM 12N-15N BETWEEN 30W-34W. SCATTERED 
MODERATE CONVECTION IS FROM 10N-14N BETWEEN 37W-41W...AND FROM 
8N-10N BETWEEN 40W-48W. 

...DISCUSSION...

THE GULF OF MEXICO...
RADAR IMAGERY SHOWS AIRMASS RAIN AND THUNDERSTORMS OVER INLAND 
FLORIDA S OF 30N. SCATTERED SHOWERS AND RAIN ARE ALSO OVER THE 
STRAITS OF FLORIDA...AND ALONG THE COAST OF LOUISIANA. MORE RAIN 
AND THUNDERSTORMS ARE INLAND OVER CUBA AND THE YUCATAN PENINSULA.
SURFACE RIDGING DOMINATES THE GULF OF MEXICO WITH 10-15 KT E-SE 
WINDS. MOSTLY FAIR WEATHER IS OVER THE REMAINDER OF THE GULF. 
EXPECT SHOWERS AND RAIN TO ADVECT CONVECTION OVER THE SOUTH 
CENTRAL GULF AND THE BAY OF CAMPECHE OVER THE NEXT 24 HOURS. 
ALSO EXPECT MORE RAIN AND THUNDERSTORMS OVER FLORIDA...CUBA ... 
AND THE YUCATAN PENINSULA OVER THE NEXT 24 HOURS.     

THE CARIBBEAN SEA...
SCATTERED MODERATE TO ISOLATED STRONG CONVECTION IS OVER THE E 
CARIBBEAN FROM 14N-19N BETWEEN 63W-69W TO INCLUDE THE LEEWARD 
ISLANDS...PUERTO RICO...AND E HISPANIOLA. A SURFACE TROUGH IS 
OVER THE CENTRAL CARIBBEAN FROM 21N78W TO 13N79W. WIDELY 
SCATTERED MODERATE CONVECTION IS WITHIN 120 NM OF THE TROUGH 
AXIS TO INCLUDE E CUBA AND JAMAICA. THE MONSOON TROUGH EXTENDS 
FROM N COLOMBIA TO S COSTA RICA. SCATTERED MODERATE CONVECTION 
IS FROM 7N-10N BETWEEN 77W-84W. ELSEWHERE...SCATTERED MODERATE 
TO STRONG CONVECTION IS INLAND OVER VENEZUELA FROM 7N-12N 
BETWEEN 65W-72W. 10-20 KT TRADEWINDS ARE OVER THE CARIBBEAN WITH 
STRONGEST WINDS ALONG THE COAST OF N COLOMBIA. EXPECT THE 
SURFACE TROUGH 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...
RADAR IMAGERY SHOWS SCATTERED SHOWERS AND RAIN ALONG THE COAST 
OF FLORIDA AND THE N BAHAMAS. A 1010 MB LOW IS OVER THE WESTERN  
TROPICAL ATLANTIC NEAR 18N50W. SCATTERED MODERATE CONVECTION IS 
FROM 17N-19N BETWEEN 49W-51W. A 1025 MB HIGH IS OVER THE E 
ATLANTIC NEAR 39N19W. A SURFACE RIDGE AXIS EXTENDS SW FROM THE 
HIGH TO 25N35W. IN THE UPPER LEVELS AN UPPER LEVEL LOW IS 
CENTERED E OF THE CENTRAL BAHAMAS NEAR 25N73W. SCATTERED SHOWERS 
AND ISOLATED THUNDERSTORMS ARE FROM 21N-28N BETWEEN 63W-73W. 
EXPECT THE SURFACE LOWS OVER THE TROPICS TO BE THE DOMINATE 
WEATHER PRODUCERS OVER THE NEXT 24 HOURS AS THEY MOVE W.   

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

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FORMOSA