[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 211138
TWDAT

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
705 AM EST THU JAN 21 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY
THROUGH 1115 UTC.

...THE ITCZ...
FROM THE LIBERIA COAST NEAR 7N10W TO 3N20W 2N30W...CROSSING THE
EQUATOR ALONG 38W...INTO NORTHEASTERN BRAZIL NEAR 4S45W.
ISOLATED MODERATE SHOWERS ARE TO THE SOUTH OF 6N TO THE EAST OF
37W. HIGH CLOUDS FROM THE EQUATOR TO 20N BETWEEN AFRICA AND 33W
ARE MOVING TOWARD THE NORTH AND NORTHEAST.

...DISCUSSION...

THE GULF OF MEXICO...
UPPER LEVEL NORTHWESTERLY WIND FLOW MOVES ACROSS INTERIOR MEXICO
INTO THE GULF OF MEXICO. SOME OF THIS FLOW MOVES AWAY FROM
A CYCLONIC CIRCULATION CENTER THAT IS MOVING FROM CENTRAL
OKLAHOMA INTO NORTHWESTERN ARKANSAS. HIGH LEVEL MOISTURE IS
BEING PUSHED INTO AN AREA THAT EARLIER WAS COVERED BY DRY AIR
IN SUBSIDENCE...COVERING THE GULF TO THE NORTHEAST OF THE LINE
FROM THE MIDDLE TEXAS COAST TO WESTERN CUBA. SOUTHERLY SURFACE
WIND FLOW COVERS THE AREA. COLD CLOUD TOP TEMPERATURES AND
SHOWERS/POSSIBLE THUNDERSTORMS COVER THE U.S.A. GULF COAST
STATES FROM 30N NORTHWARD BETWEEN 83W AND 87W...MEANING THE
WESTERN FLORIDA PANHANDLE...SOUTHERN GEORGIA...AND ALABAMA.
UPPER LEVEL SOUTHWESTERLY WIND FLOW MOVES FROM THE NORTHWESTERN
CARIBBEAN SEA ACROSS CUBA AND ACROSS THE PART OF THE BAHAMAS
THAT IS TO THE SOUTH OF 24N. THIS FLOW ON WATER VAPOR
IMAGERY...COMBINED WITH THE NORTHWESTERLY FLOW IN THE GULF OF
MEXICO...GIVES THE IMPRESSION THAT THE BASE OF A TROUGH IS ON
TOP OF THE BAHAMAS WHEN IN ACTUALITY THAT PROBABLY IS NOT THE
CASE.

THE CARIBBEAN SEA...
BROAD UPPER LEVEL SOUTHWESTERLY WIND FLOW COVERS THE
NORTHWESTERN CORNER OF THE AREA...FROM THE GULF OF HONDURAS
ACROSS CUBA AND THE BAHAMAS INTO THE ATLANTIC OCEAN.
A MIDDLE LEVEL RIDGE EXTENDS FROM THE ATLANTIC OCEAN NEAR
23N33W TO 18N56W INTO THE CENTRAL CARIBBEAN SEA. A SURFACE
TROUGH EXTENDS FROM 20N61W INTO THE NORTHEASTERN CARIBBEAN SEA
NEAR ANGUILLA AND SAINT MARTIN TO 16N64W. SHOWERS ARE POSSIBLE
FROM THE ATLANTIC OCEAN INTO THE CARIBBEAN SEA FROM 14N TO 20N
BETWEEN 57W AND 64W. GALE-FORCE WINDS ARE ALONG THE COAST OF
COLOMBIA FROM 11N TO 15N BETWEEN 70W AND 77W...INCLUDING SEA
HEIGHTS FROM 8 FT TO 14 FT. THIS CONDITION IS FORECAST TO
CONTINUE FOR THE NEXT 24 HOURS TO 30 HOURS.

THE ATLANTIC OCEAN...
A MIDDLE LEVEL RIDGE EXTENDS FROM THE ATLANTIC OCEAN NEAR 26N25W
TO 23N33W TO 18N56W INTO THE CENTRAL CARIBBEAN SEA. THE BROAD
UPPER LEVEL ANTICYCLONIC FLOW COVERS THE ATLANTIC OCEAN TO THE
WEST OF 30W. AN UPPER LEVEL TROUGH/SHEAR AXIS IS ALONG 25N16W
21N24W...AND A TROUGH CONTINUES FROM 21N24W TO 17N32W TO 14N33W
5N34W. BROAD UPPER LEVEL CYCLONIC FLOW COVERS THE AREA FROM 5N
TO 20N BETWEEN 30W AND 60W. AN UPPER LEVEL EASTERN ATLANTIC
OCEAN TROUGH SUPPORTS THE COLD FRONT THAT PASSES THROUGH 32N34W
TO 28N46W...CONTINUING AS A STATIONARY FRONT FROM 28N46W TO
25N58W AND 20N69W. PRECIPITATION IS NOT APPARENT WITH THIS
FRONTAL BOUNDARY. SURFACE ANTICYCLONIC FLOW IS AROUND A RIDGE
THAT PASSES THROUGH 32N15W TO 27N28W TO 24N46W AND 23N56W.

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

$$
MT





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