000
AXNT20 KNHC 040551
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL  
105 AM EST SAT DEC 04 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY
THROUGH 0515 UTC.

...THE ITCZ...
 
FROM THE COAST OF GUINEA NEAR 10N14W TO 6N21W TO 4N40W...INTO 
NORTHEASTERN BRAZIL AND EASTERN FRENCH GUIANA NEAR 4N52W.
STRONG RAINSHOWERS AND THUNDERSTORMS ARE FROM 4N TO 7N BETWEEN
45W AND 51W...AND FROM 1N TO 2N BETWEEN 46W AND 47W.
ISOLATED MODERATE RAINSHOWERS ARE ELSEWHERE TO THE SOUTH OF 10N
BETWEEN 40W AND 52W...AND FROM 2N TO 8N BETWEEN 23W AND 28W.

...DISCUSSION...

THE GULF OF MEXICO...
MEXICO FINDS ITSELF ON THE EASTERN SIDE OF AN UPPER LEVEL RIDGE
THAT CURVES FROM NEVADA AND ARIZONA...THROUGH NORTHWESTERN 
MEXICO...INTO THE EASTERN PACIFIC OCEAN NEAR 16N110W. UPPER LEVEL
NORTHWESTERLY WIND FLOW COVERS THE GULF OF MEXICO. THIS FLOW
PATTERN IS DUE TO THE POSITIONING OF BEING ON THE EASTERN SIDE
OF THE RIDGE/THE WESTERN SIDE OF THE UPPER LEVEL TROUGH THAT
SUPPORTS THE CURRENT WESTERN ATLANTIC OCEAN TROUGH. SURFACE
ANTICYCLONIC WIND FLOW MOVES AROUND A 1023 MB HIGH PRESSURE 
CENTER THAT IS NEAR 28N90W. AN EAST-TO-WEST ORIENTED COLD FRONT
ENTERS THE NORTHERN HALF OF THE GULF OF MEXICO AFTER ABOUT
THE NEXT 36 HOURS.

THE CARIBBEAN SEA...
MIDDLE LEVEL TO UPPER LEVEL CYCLONIC FLOW REMAINS IN THE 
NORTHWESTERN CORNER OF THE AREA. THIS CYCLONIC FLOW IS RELATED 
TO THE WESTERN ATLANTIC OCEAN TROUGH THAT SUPPORTS THE COLD 
FRONT THAT PASSES THROUGH THE TURKS AND CAICOS ISLANDS...TO 
EXTREME SOUTHEASTERN CUBA...INTO THE CARIBBEAN SEA NEAR 
19N80W...CURVING INTO EASTERN HONDURAS. THE UPPER LEVEL FLOW
IS SOLIDLY FROM THE SOUTHWEST IN THE AREA THAT IS TO THE EAST
OF THE LINE THAT GOES FROM NICARAGUA BEYOND HISPANIOLA.
THE SURFACE WIND FLOW IS MOSTLY NORTHEASTERLY ACROSS THE AREA.

THE ATLANTIC OCEAN...
THE DEEP LAYER TROUGH THAT IS IN THE WESTERN ATLANTIC OCEAN
SUPPORTS THE COLD FRONT THAT PASSES THROUGH 32N59W TO 25N66W...
ACROSS THE TURKS AND CAICOS ISLANDS...AND BEYOND EXTREME 
SOUTHEASTERN CUBA AND 19N80W IN THE NORTHWESTERN CARIBBEAN SEA 
TO EASTERN HONDURAS. RAINSHOWERS ARE POSSIBLE WITHIN 60 NM TO
90 NM ON EITHER SIDE OF 32N57W 28N69W 24N65W 21N70W 20N74W AT
THE COAST OF CUBA. COLD-AIR STRATIFORM CLOUDS COVER THE ATLANTIC 
OCEAN TO THE NORTHWEST OF THE COLD FRONT. A CYCLONIC CIRCULATION 
CENTER IN WATER VAPOR IMAGERY IS NEAR 36N31W. A TROUGH EXTENDS 
FROM 36N31W TO 29N32W 23N35W TO 13N39W. A 985 MB GALE LOW 
PRESSURE CENTER IS NEAR 36N33W. ONE COLD FRONT THAT ULTIMATELY
CURVES AWAY FROM THE GALE LOW PRESSURE CENTER PASSES THROUGH
32N23W TO 21N30W AND 14N39W. A SECOND COLD FRONT IS WITHIN
200 NM TO 360 NM TO THE WEST OF THE FIRST FRONT. A SURFACE TROUGH
STILL IS PART OF THE ENTIRE SYSTEM...PASSING THROUGH 32N31W TO
30N33W AND 27N40W. RAINSHOWERS ARE TO THE NORTH OF 29N BETWEEN 
27W AND 33W...AND TO THE NORTH OF 24N BETWEEN THE CANARY ISLANDS 
AND 26W.

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

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MT