000
AXNT20 KNHC 021755
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL  
105 PM EST WED DEC 02 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...

9N13W 5N30W 5N40W...INTO NORTHEASTERN BRAZIL NEAR 4N51W. 
ISOLATED AND DISORGANIZED MODERATE SHOWERS FROM 3N TO 8N
BETWEEN 19W AND 25W...TO THE SOUTH OF 6N BETWEEN 25W AND
50W...AND TO THE SOUTH OF 10N BETWEEN 50W AND 60W.

...DISCUSSION...

THE GULF OF MEXICO...
AN UPPER LEVEL TROUGH EXTENDS FROM BROAD CYCLONIC FLOW CENTERED
FROM ARKANSAS TO NORTHERN LOUISIANA...TO 26N95W IN THE 
NORTHWESTERN CORNER OF THE AREA...TO 22N96W. THIS TROUGH
SUPPORTS A COLD FRONT THAT PASSES THROUGH THE MISSISSIPPI/
ALABAMA BORDER NEAR 30N88W TO THE CENTRAL GULF OF MEXICO NEAR
25N90W...TO THE SOUTHWESTERN CORNER AND COASTAL PLAINS OF MEXICO
NEAR 20N97W. THE WARM FRONT THAT WAS PART OF THE SURFACE FRONTAL
BOUNDARY FROM 24 HOURS AGO HAS MOVED TO THE NORTH OF THE U.S.A.
GULF COASTAL STATES.ISOLATED TO WIDELY SCATTERED MODERATE
SHOWERS AND POSSIBLE THUNDERSTORMS ARE WITHIN 30 NM TO 45 NM
ON EITHER SIDE OF 22N92W 25N88W 27N86W BEYOND 30N84W JUST
TO THE EAST OF THE FLORIDA BIG BEND. GALE FORCE WINDS ARE
PRESENT TO THE NORTH OF 27N TO THE EAST OF 94W.

THE CARIBBEAN SEA...
BROAD SURFACE EASTERLY WIND FLOW COVERS THE AREA TO THE EAST OF 
80W. THE FLOW CURVES NORTHWESTWARD TOWARD CUBA AND THE YUCATAN 
CHANNEL TO THE NORTH OF 14N TO THE WEST OF 80W. THE SURFACE FLOW 
BECOMES CYCLONIC TO THE SOUTH OF 14N TO THE WEST OF 80W.
BROAD UPPER LEVEL ANTICYCLONIC FLOW AND DRY AIR IN SUBSIDENCE
CONTINUE TO COVER THE AREA...BRINGING FAIR WEATHER.

THE ATLANTIC OCEAN...
BROAD UPPER LEVEL ANTICYCLONIC FLOW COVERS THE AREA TO THE WEST
OF 50W. A DEEP LAYER CENTRAL ATLANTIC OCEAN TROUGH...THAT IS 
ALONG 45W/46W FROM 18N BEYOND 32N...SUPPORTS THE SURFACE TROUGH 
THAT PASSES THROUGH 32N45W TO 26N48W TO 20N52W. ISOLATED TO 
WIDELY SCATTERED MODERATE SHOWERS AND POSSIBLE THUNDERSTORMS ARE
WITHIN 100 NM ON EITHER SIDE OF 16N47W 26N44W BEYOND 32N43W.
A COLD FRONT THAT PASSES THROUGH 32N52W TO 30N61W...BECOMING
A WARM FRONT AND CONTINUING FROM 30N61W TO 29N70W BEYOND 32N78W.
IT DOES NOT APPEAR THAT THIS FRONTAL BOUNDARY HAS MUCH UPPER 
LEVEL SUPPORT...AT LEAST BY LOOKING AT THE WATER VAPOR SATELLITE 
IMAGERY. GFS MODEL INFORMATION FOR 500 MB AND FOR 700 MB ALSO 
SHOW ONLY A TROUGH IN THE CENTRAL ATLANTIC OCEAN THAT IS 
CONSISTENT WITH THE 45W/46W TROUGH. AN UPPER LEVEL TROUGH PASSES 
THROUGH 32N12W...ACROSS THE CANARY ISLANDS TO 23N30W TO 15N40W. 
NO DEEP CONVECTIVE PRECIPITATION ACCOMPANIES THIS TROUGH.

$$
FG/MT