000
AXNT20 KNHC 201151
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL  
705 AM EST SAT NOV 20 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1015 UTC.

...THE ITCZ...
 
ITCZ AXIS IS ANALYZED ALONG 7N12W 7N20W 5N30W 5N38W 4N43W 3N52W. 
A SURFACE TROUGH IS EMBEDDED WITHIN THE ITCZ FROM 12N38W TO 
1N40W. SCATTERED STRONG CONVECTION IS FROM 3N-7N BETWEEN 22W-30W 
AND WITHIN 90 NM S OF THE ITCZ BETWEEN 34W-37W. CLUSTERS OF 
SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE FROM THE ITCZ 
TO 10N BETWEEN 27W-40W...WITHIN 200 NM S OF THE ITCZ BETWEEN 
30W-38W...AND FROM 6N-12N BETWEEN 40W-50W. 

...DISCUSSION...

GULF OF MEXICO...
BROAD UPPER RIDGE ANCHORED IN THE CARIBBEAN COVERS THE AREA 
GIVING THE ENTIRE GULF SW TO W FLOW ALOFT WITH MODERATE 
SUBSIDENCE AND MOSTLY DRY STABLE AIR ALOFT AS NOTED IN WATER 
VAPOR IMAGERY. A BROAD SURFACE RIDGE DOMINATES THE GULF WITH A 
WEAKNESS IN THE VICINITY OF A SURFACE TROUGH THAT EXTENDS FROM 
SE MISSISSIPPI ACROSS MOBILE BAY ALABAMA ALONG 29N88W TO 28N88W. 
ISOLATED SHOWERS ARE WITHIN 60 NM E OF THE SURFACE TROUGH. 
ISOLATED SHOWERS REMAIN WITHIN 90 NM ALONG THE COAST OF MEXICO 
FROM VERA CRUZ TO N OF TAMPICO AND WITHIN 45 NM ALONG THE COAST 
IN THE E BAY OF CAMPECHE S OF 20N E OF 94W LEAVING THE REMAINDER 
OF THE GULF WITH FAIR CONDITIONS THIS MORNING. 

CARIBBEAN SEA...
A WEAKENING STATIONARY FRONT REMAINS OVER THE W CARIBBEAN 
EXTENDING ACROSS CENTRAL CUBA NW OF CAMAGUEY ALONG 20N84W TO THE 
GULF OF HONDURAS NEAR 16N87W WITH SCATTERED SHOWERS/ISOLATED 
THUNDERSTORMS S OF 19N W OF THE FRONT TO INLAND OVER THE YUCATAN 
AND ISOLATED SHOWERS WITHIN 120 NM E OF THE FRONT. A SURFACE 
TROUGH IS OVER THE E CARIBBEAN EXTENDING FROM 16N65W TO THE 
ISLANDS OFF THE COAST OF VENEZUELA NEAR 12N67W WITH SCATTERED 
SHOWERS/ISOLATED THUNDERSTORMS FROM 12N-15N BETWEEN 63W-67W AND 
ISOLATED SHOWERS OVER THE REMAINDER OF THE AREA FROM 11N-17N E 
OF 68W TO OVER THE WINDWARD ISLANDS. BROAD UPPER RIDGE COVERS 
THE ENTIRE CARIBBEAN AND EXTENDING OVER THE GULF OF MEXICO 
ANCHORED S OF HAITI NEAR 17N73W. THIS UPPER RIDGE IS PROVIDING 
DIFFLUENCE ALOFT TO ENHANCE THE ACTIVITY ASSOCIATED WITH THE 
ABOVE SURFACE TROUGH AND GENERATE SCATTERED SHOWERS/ISOLATED 
THUNDERSTORMS FROM 10N-15N BETWEEN 69W-78W INCLUDING TO COAST OF 
NW VENEZUELA AND N COLOMBIA. ISOLATED SHOWERS ARE ALSO IN THE SW 
CARIBBEAN S OF A LINE FROM JUST S OF CARTAGENA COLOMBIA TO PUNTA 
GORDA NICARAGUA. 

ATLANTIC OCEAN...
BROAD UPPER LEVEL TROUGH COVERS THE W ATLC N OF 23N W OF 45W 
SUPPORTING A COLD FRONT THAT ENTERS THE REGION NEAR 32N52W 
EXTENDING SW ALONG 25N62W THROUGH THE S BAHAMA ISLANDS NEAR 
23N73W BECOMING STATIONARY ACROSS CENTRAL CUBA NW OF CAMAGUEY 
INTO THE W CARIBBEAN. SCATTERED SHOWERS ARE WITHIN 90/120 NM SE 
OF THE FRONT. A WEAKENING CUT-OFF UPPER LOW IS OVER THE 
E/CENTRAL ATLC CENTERED NEAR 26N38W SUPPORTING A SURFACE TROUGH 
THAT EXTENDS FROM 27N43W TO 22N47W AND NO SIGNIFICANT WEATHER. A 
HIGH AMPLITUDE UPPER RIDGE IS JUST TO THE E EXTENDING FROM THE 
TROPICS NEAR 7N27W TO BEYOND 32N20W PROVIDING DIFFLUENCE ALOFT 
TO ENHANCE SCATTERED SHOWERS WITHIN 150 NM ON OF LINE FROM 
20N34W TO 30N34W. A SURFACE RIDGE COVERS THE E ATLC N OF 23N E 
OF 33W ANCHORED BY A 1020 MB HIGH W OF THE CANARY ISLANDS NEAR 
30N21W. 

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

$$
PAW