000
AXNT20 KNHC 060002
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL  
705 PM EST SAT DEC 05 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY
THROUGH 2315 UTC.

...ITCZ...

FROM 7N10W IN AFRICA TO 6N20W 4N30W 1N40W INTO EXTREME
NORTHEASTERN BRAZIL NEAR 1N53W. ISOLATED MODERATE SHOWERS
FROM THE EQUATOR TO TO 6N BETWEEN 14W AND 45W.

...DISCUSSION...

FROM THE WESTERN ATLANTIC OCEAN...ACROSS SOUTH FLORIDA...
INTO THE GULF OF MEXICO INTO THE NORTHWESTERN CARIBBEAN SEA...
THE UPPER LEVEL TROUGH THAT SUPPORTS THE CURRENT COLD FRONT THAT 
IS MOVING THROUGH THE EXTREME SOUTHEASTERN GULF OF MEXICO PASSES
THROUGH SOUTH CAROLINA...EASTERN GEORGIA...AND NORTHWESTERN 
FLORIDA...INTO THE SOUTH CENTRAL GULF OF MEXICO. COMPARATIVELY 
DRIER AIR ON WATER VAPOR IMAGERY IS WITHIN 400 NM TO 600 NM TO
THE WEST OF THE LINE THAT PASSES THROUGH 31N76W 27N82W 25N86W.
THE COLD FRONT PASSES THROUGH 31N76W TO SOUTH FLORIDA JUST TO 
THE SOUTH OF LAKE OKEECHOBEE TOWARD KEY WEST...ACROSS WESTERN 
CUBA...INTO THE NORTHWESTERN CARIBBEAN SEA...TO THE SOUTHEASTERN
YUCATAN PENINSULA. ISOLATED MODERATE SHOWERS TO POSSIBLE 
THUNDERSTORMS ARE WITHIN 60 NM TO 90 NM ON EITHER SIDE OF THE 
LINE THROUGH 23N81W ALONG THE NORTHERN CUBA COAST...28N76W
BEYOND 31N73W. SHOWERS ARE POSSIBLE WITHIN 30 NM ON EITHER SIDE 
OF 22N82W IN WESTERN CUBA TO 20N85W TO 16N87W. SURFACE HIGH 
PRESSURE HAS BEEN SPREADING ACROSS THE GULF OF MEXICO TO THE 
WEST OF THE COLD FRONT. 

THE REST OF THE CARIBBEAN SEA...
UPPER LEVEL DRY AIR IN SUBSIDENCE IS EVERYWHERE. BROAD EASTERLY 
SURFACE FLOW COVERS THE AREA FROM THE EASTERN CARIBBEAN SEA 
ISLANDS TO 70W. THE FLOW BECOMES CYCLONIC TO THE SOUTH OF 
HISPANIOLA AND JAMAICA BETWEEN 70W AND CENTRAL AMERICA.
SHOWERS ARE POSSIBLE FROM 15N TO PUERTO RICO AND 20N BETWEEN
64W AND 68W...FROM 16N TO HISPANIOLA BETWEEN 70W AND 74W...
WITHIN 30 NM ON EITHER SIDE OF 17N75W 15N79W 13N80W 12N81W...
WITHIN A 20 NM RADIUS OF 17N81W...FROM HONDURAS TO 17N BETWEEN
83W AND 86W...AND WITHIN 60 NM OF THE COASTS OF PANAMA...
COSTA RICA...AND NICARAGUA BETWEEN 80W AND 84W.

THE REST OF THE ATLANTIC OCEAN...
BROAD UPPER LEVEL ANTICYCLONIC FLOW AND DRY AIR IN SUBSIDENCE 
COVER THE ATLANTIC OCEAN TO THE NORTH OF 20N TO THE WEST OF 40W.
AN UPPER LEVEL TROUGH PASSES THROUGH 32N33W TO 27N37W. A SHEAR
AXIS CONTINUES FROM 27N37W TO 23N43W AND 22N50W. THIS TROUGH 
SUPPORTS A SURFACE TROUGH THAT GOES FROM 31N33W TO 27N40W TO 
25N46W. SHOWERS ARE POSSIBLE WITHIN 60 NM ON EITHER SIDE OF THE 
LINE THAT PASSES THROUGH 32N27W TO 28N34W. AN UPPER LEVEL TROUGH
EXTENDS FROM WESTERN ALGERIA/EASTERN MOROCCO TO 25N16W IN THE 
ATLANTIC OCEAN...TO 20N35W TO A CYCLONIC CIRCULATION CENTER THAT 
IS NEAR 15N46W TO 14N56W.
 
$$
MT