000
AXNT20 KNHC 140512
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
205 AM EDT WED OCT 14 2009

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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0345 UTC.

...TROPICAL WAVES...

TROPICAL WAVE IS ALONG 58W/59W S OF 13N MOVING W NEAR 15 KT. 
WAVE IS EMBEDDED WITHIN THE ITCZ AT LOW AMPLITUDE AND WITHIN AN 
AREA OF DEEP MOISTURE AS INDICATED IN THE TOTAL PRECIPITABLE 
WATER IMAGERY. CLUSTERS OF SCATTERED MODERATE CONVECTION ARE 
FROM 10N-14N BETWEEN 56W-60W. 

...ITCZ...

THE ITCZ AXIS IS CENTERED ALONG 9N12W 8N20W 9N27W 7N33W 10N45W 
9N52W 11N58W. A SURFACE TROUGH IS EMBEDDED WITHIN THE ITCZ ALONG 
27W/28W FROM 5N-9N AND A SECOND SURFACE TROUGH ALSO EMBEDDED 
WITHIN THE ITCZ ALONG 46W/47W FROM 8N-12N. SCATTERED MODERATE/ 
STRONG CONVECTION IS FROM 9N-13N BETWEEN 43W-49W. SCATTERED 
MODERATE/ISOLATED STRONG CONVECTION IS WITHIN 90 NM ALONG THE 
COAST OF W AFRICA FROM 5N-10N. CLUSTERS OF SCATTERED MODERATE/ 
ISOLATED STRONG CONVECTION ARE FROM 5N-10N BETWEEN 20W-30W AND 
FROM 5N-9N BETWEEN 30W-37W. CLUSTERS OF SCATTERED MODERATE 
CONVECTION ARE FROM 2N-12N BETWEEN 47W-53W. 

...DISCUSSION...

GULF OF MEXICO...
THE STATIONARY FRONT THAT HAS PLAGUED THE GULF OVER THE PAST FEW 
DAYS IS FINALLY DISSIPATING OVER THE NE GULF FROM TAMPA TO THE 
CENTRAL MISSISSIPPI COAST. BROAD UPPER RIDGE CONTINUES TO 
DOMINATE THE GULF ANCHORED NEAR 26N93W AND AN AXIS EXTENDING E 
INTO THE W ATLC ACROSS FLORIDA NEAR LAKE OKEECHOBEE. MOSTLY DRY 
STABLE AIR DOMINATES THE AREA WITH SOME LOW LEVEL WIDELY 
ISOLATED SHOWERS DOTTING THE AREA N OF 25N AND DENSE LOW LEVEL 
CLOUDS ARE OVER THE FAR NE GULF N OF 28N E OF 86W. THE REMAINDER 
OF THE GULF IS EXPERIENCING FAIR WEATHER WITH CLEAR SKIES AGAIN 
TONIGHT. A SURFACE RIDGE CONTINUES TO SLOWLY BUILD WESTWARD. 

CARIBBEAN SEA...
THE BROAD UPPER RIDGE THAT COVERS MOST OF THE ATLC AND GULF OF 
MEXICO IS GIVING MOST OF THE CARIBBEAN UPPER EASTERLY WINDS N OF 
A SHEAR AXIS THAT ENTERS THE CARIBBEAN OVER THE LESSER ANTILLES 
NEAR MARTINIQUE ALONG 13N72W TO PANAMA NEAR 9N78W PRODUCING 
SCATTERED SHOWERS/ISOLATED THUNDERSTORMS WITHIN 90 NM OF LINE 
FROM HAITI NEAR 19N92W ALONG THE S COAST OF CUBA TO NEAR 22N84W 
AND IN THE SW CARIBBEAN S OF 12N W OF 80W TO INLAND OVER CENTRAL 
AMERICA. WIDELY ISOLATED LOW LEVEL SHOWERS DOT THE N CARIBBEAN N 
OF 16N WHILE THE REMAINDER OF THE CARIBBEAN IS UNDER A VERY DRY 
AND STABLE AIRMASS GIVING THAT AREA CLEAR SKIES AGAIN TONIGHT. 

ATLANTIC OCEAN...
A COLD FRONT ENTERS THE REGION NEAR 32N69W EXTENDING W TO OVER 
THE FLORIDA PENINSULA NEAR MELBOURNE WHERE IT DISSIPATES OVER 
THE NE GULF OF MEXICO. THE UPPER LEVEL TROUGH SUPPORTING THIS 
FRONT REMAINS N OF THE REGION BUT COUPLED WITH THE BROAD UPPER 
RIDGE THAT DOMINATES THE ATLC W OF 40W AND THE AXIS EXTENDING 
FROM ACROSS THE GULF AND THE FLORIDA PENINSULA N OF LAKE 
OKEECHOBEE TO NEAR 25N40W IS PROVIDING DIFFLUENCE ALOFT TO 
GENERATE SCATTERED SHOWERS/ISOLATED THUNDERSTORMS N OF 30N 
BETWEEN 53W-65W. A SHARP UPPER TROUGH DIGS S INTO THE E ATLC 
NEAR 32N30W S TO 20N34W THEN EXTENDS W AS A SHEAR AXIS ALONG 
17N51W OVER THE LESSER ANTILLES NEAR MARTINIQUE INTO THE S 
CARIBBEAN. THIS UPPER TROUGH CONTINUES TO SUPPORT A 1012 MB 
SURFACE LOW CENTERED NEAR 31N33W AND A SURFACE TROUGH EXTENDING 
S ALONG 27N33W THEN SW TO 24N45W AND SECOND SURFACE TROUGH TO 
THE E FROM 32N23W EXTENDING ALONG 28N25W TO 25N32W. SCATTERED 
SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS ARE N OF 24N BETWEEN 
21N24W. 
 
$$
WALLACE