000
AXNT20 KNHC 201756
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
105 PM EST FRI FEB 20 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1715 UTC.

...THE ITCZ...

THE ITCZ AXIS IS CENTERED ALONG 5N8W 3N11W CROSSING THE EQUATOR 
NEAR 17W EXTENDING TO 3S25W 4S34W INTO NE BRAZIL NEAR 5S38W. 
SCATTERED MODERATE CONVECTION IS S OF 5N BETWEEN 13W-21W. 
SCATTERED MODERATE CONVECTION IS ALSO S OF 2N BETWEEN 26W-33W.

...DISCUSSION...

GULF OF MEXICO...
STRONG WESTERLY FLOW ALOFT COVERS THE GULF IN THE BASE OF A DEEP 
TROUGH OVER THE E CONUS AND W ATLC. A COLD FRONT ASSOCIATED WITH 
THIS TROUGH IS PRESENT ACROSS THE S GULF AND EXTENDS FROM W 
CUBA NEAR 22N84W TO NW OF THE YUCATAN PENINSULA NEAR 21N91W 
ACROSS THE BAY OF CAMPECHE TO THE MEXICO COAST NEAR 18N93W. LOW 
LEVEL CONVERGENCE IS SUPPORTING SCATTERED SHOWERS WITHIN 60 NM 
EITHER SIDE OF THE FRONT. N OF THE FRONT TO 27N W OF 84W...A 
LAYER OF SCATTERED TO OVERCAST STRATOCUMULUS CLOUDS IS PRESENT 
IN RESPONSE TO COLD AIR ADVECTION OVER RELATIVELY WARMER GULF 
WATERS. ACROSS THE N GULF...MOSTLY CLEAR SKIES ARE PRESENT WHERE 
SUBSIDENCE IS OCCURRING IN THE VICINITY OF A 1028 MB SURFACE 
HIGH IN W LOUISIANA NEAR 32N93W.

CARIBBEAN SEA...
THE SURFACE COLD FRONT OVER THE S GULF OF MEXICO WILL ENTER THE 
YUCATAN CHANNEL DURING THE NEXT DAY AND IS FORECAST TO MOVE 
ACROSS THE NW CARIBBEAN THROUGH TONIGHT. FRESH TO STRONG TRADE 
WINDS ARE FORECAST TO CONTINUE INTO TUESDAY WITH AN INCREASED 
PRESSURE GRADIENT ACROSS THE CARIBBEAN. THE STRONGEST WINDS ARE 
FOUND ALONG THE COAST OF COLOMBIA...WHERE A GALE WARNING IS IN 
EFFECT. GENERALLY FAIR WEATHER CONDITIONS ARE PRESENT ACROSS THE 
CARIBBEAN REGION WITH AN UPPER RIDGE DOMINATING THE REGIONAL 
WEATHER. PATCHES OF LOW LEVEL MOISTURE CONTINUE TO BE ADVECTED 
EASTWARD ACROSS THE CARIBBEAN ON EASTERLY TRADE WINDS...WITH 
SCATTERED SHOWERS EMBEDDED WITHIN THESE PATCHES OF LOW LEVEL 
MOISTURE. THE GREATEST CONCENTRATION OF THESE SHOWERS IS FROM 
16N-19N W OF 78W. 

ATLANTIC OCEAN...
THE DEEP TROUGH OVER THE E CONUS AND W ATLC CONTINUES TO 
PROGRESS EASTWARD WITH AN ASSOCIATED COLD FRONT EXTENDING FROM 
NE OF THE DISCUSSION AREA TO 32N68W TO 28N74W TO W CUBA NEAR 
23N82W. LOW LEVEL CONVERGENCE IS SUPPORTING SCATTERED SHOWERS 
WITHIN 90 NM EITHER SIDE OF THE FRONT. FARTHER TO THE E...A 1030 
MB SURFACE HIGH IS CENTERED NEAR 33N44W. SUBSIDENCE IS 
SUPPORTING FAIR WEATHER CONDITIONS IN THE VICINITY OF THIS 
SURFACE HIGH. FARTHER TO THE E...A DISSIPATING SURFACE 
STATIONARY FRONT ENTERS THE DISCUSSION AREA NEAR 32N33W AND 
EXTENDS TO 28N39W WITH A SURFACE TROUGH EXTENDING FROM 28N39W TO 
23N52W. LOW LEVEL CONVERGENCE IS SUPPORTING INCREASED CLOUDINESS 
AND ISOLATED SHOWERS WITHIN 60 NM EITHER SIDE OF THIS SURFACE 
FRONT AND SURFACE TROUGH. ACROSS THE E ATLC...SUBSIDENCE 
ASSOCIATED WITH A SURFACE RIDGE IS RESULTING IN GENERALLY FAIR 
WEATHER CONDITIONS. ACROSS THE TROPICAL ATLC...AN UPPER RIDGE IS 
PRESENT S OF 9N BETWEEN 12W-35W...AND UPPER LEVEL DIVERGENCE 
ASSOCIATED WITH THIS UPPER RIDGE IS ENHANCING THE CONVECTION 
ASSOCIATED WITH THE ITCZ.

$$
COHEN