AXNT20 KNHC 081155
TWDAT 

TROPICAL WEATHER DISCUSSION
TPC/NATIONAL HURRICANE CENTER MIAMI FL
705 AM EST THU JAN 08 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY
THROUGH 1115 UTC.

...THE ITCZ...

FROM LIBERIA NEAR 7N9W TO 3N20W 2N30W 2N40W...TO NORTHEASTERN 
BRAZIL NEAR 1N51W. ISOLATED MODERATE SHOWERS TO LOCALLY STRONG 
THUNDERSTORMS ARE SOUTH OF 4N EAST OF 40W. SCATTERED MODERATE 
SHOWERS TO ISOLATED STRONG THUNDERSTORMS ARE FROM THE EQUATOR
TO 2N BETWEEN 50W AND 52W. 

...DISCUSSION...

THE GULF OF MEXICO...THE ATLANTIC OCEAN WEST OF 70W...
AND THE NORTHWESTERN CARIBBEAN SEA...
DEEP LAYER CYCLONIC FLOW COVERS THE GULF OF MEXICO NORTH OF 25N
AND ELSEWHERE OVER THE U.S.A. EAST OF 100W. THE TROUGH THAT IS 
BRINGING ABOUT THIS CYCLONIC FLOW NOW IS PROVIDING ENERGY TO 
WHAT WAS THE SLOWLY-MOVING SHALLOW COLD FRONT THAT HAS BEEN
IN THE GULF OF MEXICO FOR THE LAST FEW DAYS. THIS COLD FRONT
FINALLY HAS SWEPT ACROSS THE GULF OF MEXICO...AND NOW IT PASSES 
THROUGH 32N72W IN THE ATLANTIC OCEAN...TO ANDROS ISLAND IN THE 
BAHAMAS...TO WESTERN CUBA...TO BELIZE. UPPER LEVEL SOUTHWESTERLY 
WIND FLOW STARTS IN THE SOUTHWESTERN CORNER OF THE AREA...MOVES 
TO THE CENTRAL GULF WATERS...AND EXITS THE AREA ACROSS SOUTH
FLORIDA...MOVING BEYOND 32N70W. GALE FORCE WINDS OR NEAR-GALE 
FORCE WINDS ARE FORECAST IN THE ATLANTIC OCEAN FOR THE NEXT
48 HOURS NORTH OF 29N WITHIN 180 NM TO THE EAST OF THE COLD 
FRONT AND SEA HEIGHTS RANGING FROM 10 FT TO 15 FT.
A 1018 MB HIGH PRESSURE CENTER IS NEAR 26N90W.

THE CARIBBEAN SEA...
UPPER LEVEL ANTICYCLONIC FLOW COVERS THE AREA WEST OF 75W.
THIS ANTICYCLONIC FLOW IS RELATED TO THE ATLANTIC OCEAN UPPER 
LEVEL RIDGE THAT EXTENDS FROM HISPANIOLA BEYOND 32N60W.
MIDDLE TO UPPER LEVEL CYCLONIC FLOW IS FORMING TO THE EAST
OF 75W...AROUND AN INVERTED TROUGH ALONG 67W/68W. UPPER
LEVEL DRY AIR IN SUBSIDENCE IS EVERYWHERE. SHOWERS ARE
POSSIBLE IN LINES OF CONFLUENT SURFACE WIND FLOW.

THE REST OF THE ATLANTIC OCEAN EAST OF 70W...
AN UPPER LEVEL RIDGE EXTENDS FROM HISPANIOLA BEYOND 32N57W.
A MIDDLE TO UPPER LEVEL TROUGH EXTENDS FROM ONE CYCLONIC 
CIRCULATION CENTER NEAR 25N37W TO A SECOND CYCLONIC CENTER
NEAR 18N46W TO 15N50W TO 8N51W. SCATTERED MODERATE SHOWERS
TO ISOLATED STRONG THUNDERSTORMS ARE FROM 6N TO 16N BETWEEN
39W AND 50W. BROAD SURFACE ANTICYCLONIC FLOW COVERS THE ATLANTIC 
OCEAN TO THE EAST OF THE 32N72W TO ANDROS ISLAND COLD FRONT.
A RIDGE IS ALONG THE LINE FROM A 1026 MB HIGH PRESSURE CENTER 
NEAR 30N43W TO 26N60W TO 22N80W JUST WEST OF CUBA. A SHORTWAVE 
TROUGH IS MOVING FROM THE ATLANTIC OCEAN TO MOROCCO AND WESTERN 
SAHARA.

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MT