000
AXNT20 KNHC 131122
TWDAT 

TROPICAL WEATHER DISCUSSION   
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
705 AM EST THU NOV 13 2008

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 
1045 UTC.

...THE ITCZ...
THE AXIS IS ANALYZED ALONG 10N10W 7N24W 9N39W 6N58W. SCATTERED 
MODERATE/ISOLATED STRONG CONVECTION IS JUST OF THE SW COAST OF 
AFRICA WITHIN 60 NM OF LINE FROM 5N11W TO 7N15W AND WITHIN 60 NM 
N OF THE ITCZ FROM 23W-26W. 

...DISCUSSION...

GULF OF MEXICO...
DEEP LAYERED TROUGH EXTENDS FROM THE CENTRAL PLAIN STATES OVER W 
MEXICO DRAWING TROPICAL MOISTURE ACROSS MEXICO OVER THE NW GULF 
WITH A STATIONARY BOUNDARY EXTENDING ACROSS S GEORGIA/S ALABAMA 
TO MOBILE BAY WHERE IT ENTERS THE GULF AS A COLD FRONT ACROSS SE 
LOUISIANA ALONG 28N95W THEN INLAND OVER BROWNSVILLE TEXAS. A 
PREFRONTAL TROUGH IS IN THE GULF WATERS FROM 28N91W TO 24N96W. 
BANDS OF SCATTERED/HEAVY SHOWERS WITH EMBEDDED THUNDERSTORMS ARE 
BETWEEN THE TROUGH AND THE COLD FRONT OVER THE GULF WATERS. A 
WEAKENING 1012 MB LOW IS ALONG THE COAST OF W CUBA NEAR BETWEEN 
HAVANA AND PINAR DEL RIO. THE REMAINDER OF THE GULF IS UNDER A 
BROAD UPPER RIDGE THAT IS ANCHORED IN THE CARIBBEAN. RETURN FLOW 
AROUND THE SURFACE RIDGE IN THE W ATLC IS GIVING THE E GULF 
SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS E OF 89W 
TO OVER THE FLORIDA PENINSULA. 

CARIBBEAN SEA...
BROAD UPPER RIDGE DOMINATES THE W CARIBBEAN ANCHORED JUST S OF 
THE CAYMAN ISLANDS COVERS THE AREA N OF 14N W OF 75W AND 
EXTENDING A RIDGE AXIS N ACROSS CUBA COVERING PORTIONS OF THE 
GULF OF MEXICO AND THE W ATLC. AN UPPER LOW OVER THE VIRGIN 
ISLANDS COVERS THE REMAINDER OF THE CARIBBEAN AND INTO THE 
W/CENTRAL ATLC GENERATING SCATTERED SHOWERS/ISOLATED 
THUNDERSTORMS OVER THE LESSER ANTILLES E OF 65W. A WEAK UPPER 
RIDGE OVER THE FAR S CARIBBEAN IS PROVIDING UPPER DIFFLUENCE AND 
COUPLED WITH LOW LEVEL CONVERGENCE IS GENERATING SCATTERED 
SHOWERS/ISOLATED THUNDERSTORMS S OF 11N BETWEEN COLOMBIA AND 
81W. THE REMAINDER OF THE CARIBBEAN IS DOMINATED BY MODERATE/ 
STRONG SUBSIDENCE AND DRY STABLE AIR BUT ISOLATED LOW LEVEL 
SHOWERS DOT MOST OF THE AREA. 

ATLANTIC OCEAN...
THE UPPER RIDGE ANCHORED IN THE W CARIBBEAN EXTENDS THE AXIS N 
OVER THE FLORIDA PENINSULA COVERING PORTIONS OF THE GULF OF 
MEXICO INTO THE W ATLC W OF 75W. A STATIONARY FRONT EXTENDS 
ACROSS THE N PORTION OF THE REGION ENTERING NEAR 32N59W W ALONG 
31N67W TO INLAND OVER S GEORGIA JUST N OF THE FLORIDA BORDER. 
SCATTERED SHOWERS ARE N OF 31N W OF 77W. A SURFACE RIDGE IS 
BUILDING OVER THE NW ATLC ANCHORED OFF THE COAST OF MAINE 
COVERING THE W ATLC N OF 26N BETWEEN 50W AND THE US E COAST. AN 
UPPER LOW IS OVER THE REMAINDER OF THE W ATLC INTO THE CENTRAL 
ATLC CENTERED OVER THE VIRGIN ISLANDS COVERING THE AREA FROM 
12N-27N BETWEEN 57W-75W WITH A SURFACE TROUGH EXTENDING FROM 
25N56W TO 18N60W. SCATTERED SHOWERS/THUNDERSTORMS ARE FROM 
19N-25N BETWEEN 55W-64W WITH SCATTERED SHOWERS/ISOLATED 
THUNDERSTORMS FROM 11N-19N BETWEEN 57W-65W INCLUDING THE LESSER 
ANTILLES. A NARROWING UPPER TROUGH IS OVER THE E/CENTRAL N OF 
22N FROM 30W-40W WITH A SURFACE TROUGH EXTENDING FROM 31N36W TO 
23N38W. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE E OF THE 
SURFACE TROUGH FROM 26N-32N BETWEEN 32W-36W. BROAD UPPER RIDGE 
COVERS THE REMAINDER OF THE E ATLC ANCHORED S OF THE EQUATOR 
PROVIDING UPPER DIFFLUENCE ENHANCING THE CONVECTION ASSOCIATED 
WITH THE ITCZ. A SECOND SURFACE RIDGE COVERS THE NE ATLC N OF 
25N E OF 30W ANCHORED NE OF THE AZORES. 

$$
WALLACE