[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 090545
TWDAT

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
105 AM EST SAT JAN 09 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.

...ITCZ...

THE ITCZ AXIS IS CENTERED ALONG 5N8W 3N21W 2N40W CROSSING THE
EQUATOR NEAR 48W. CLUSTERS OF SCATTERED MODERATE CONVECTION ARE
FROM 2N-5N BETWEEN 9W-13W.

...DISCUSSION...

GULF OF MEXICO...
AS OF 0300 UTC...THE COLD FRONT CROSSES S FLORIDA NEAR FORT
LAUDERDALE AND THE LOWER FLORIDA KEYS TO THE NE YUCATAN
PENINSULA NEAR 21N87W. A DEEP LAYERED TROUGH IS OVER THE E US TO
NEAR THE N GULF COAST BUT IS BEING OVERRIDDEN BY A STRONG UPPER
RIDGE THAT IS ANCHORED IN THE CARIBBEAN COVERING THE GULF WATERS
WITH SW UPPER FLOW. THIS UPPER FLOW IS DRAWING TROPICAL MOISTURE
ACROSS S MEXICO AND THE GULF TO OVER THE SE US INCLUDING
FLORIA...GEORGIA...ALABAMA...AND THE CAROLINAS GIVING THOSE
STATES AND THE GULF DENSE CLOUD COVER WITH ISOLATED SHOWERS. A
SURFACE RIDGE IS BUILDING BEHIND THE FRONT ANCHORED OVER THE
CENTRAL PLAIN STATES PRODUCING THE STRONG NORTHERLY SURFACE FLOW
OVER THE GULF BRINGING IN MORE COLD AIR AND COUPLED WITH THE
INDUCTION OF MOISTURE COULD GIVE PORTIONS OF N FLORIDA SNOW
FLURRIES LATER TONIGHT AND INTO SAT MORNING. THESE STRONG
NORTHERLY WINDS WILL PERSIST BEHIND THE FRONT...WITH GALE FORCE
WINDS OVER THE FAR SW GULF THROUGH TODAY THEN DIMINISH BY LATE
SUN THROUGH WED AS HIGH PRESSURE CONTINUES TO BUILD S OVER THE
GULF.

CARIBBEAN SEA...
AN UPPER LEVEL RIDGE CONTINUES TO DOMINATE THE ENTIRE CARIBBEAN
ANCHORED OVER N COLOMBIA PROVIDING A RELATIVELY SUBSIDENT
ENVIRONMENT IN THE MID TO UPPER LEVELS ACROSS MOST OF THE BASIN
WITH THE EXCEPTION OF THE FAR NW WHERE UPPER LEVEL MOISTURE IS
BEING INTRODUCED FROM THE E PACIFIC REGION. A SURFACE TROUGH IS
OVER THE FAR NW CARIBBEAN EXTENDING FROM W CUBA NEAR 22N84W TO
THE GULF OF HONDURAS NEAR 17N87W WITH DENSE CLOUD COVER AND
POSSIBLE ISOLATED SHOWERS ARE W OF THE TROUGH. A SHALLOW
STATIONARY FRONT CLIPS THE FAR NE PORTION OF THE BASIN ACROSS
THE VIRGIN ISLANDS AND SE PUERTO RICO TO NEAR 18N70W. A LOW
LEVEL SHEAR AXIS EXTENDS FROM SW HAITI ACROSS JAMAICA THEN S TO
OFF THE COAST OF NICARAGUA NEAR 13N83W DIVIDING THE LOW LEVEL
EASTERLY WINDS TO THE E AND THE NORTHERLY WINDS TO THE W. THE
COLD FRONT IN THE GULF OF MEXICO WILL MOVE INTO THE NW CARIBBEAN
LATER THIS MORNING WITH STRONG TO NEAR GALE FORCE NORTHERLY
WINDS BEHIND IT. THE FRONT WILL REACH THE MONA PASSAGE TO E
COSTA RICA BY MON EVENING WHERE IT WILL STALL OUT AND DISSIPATE
BY TUE.

ATLANTIC OCEAN...
AS OF 0300 UTC...A COLD FRONT ENTERS THE FAR W ATLC NEAR 32N73W
AND EXTENDS INTO THE GULF OF MEXICO ACROSS FLORIDA NEAR FORT
LAUDERDALE TO OVER THE LOWER FLORIDA KEYS. ISOLATED SHOWERS ARE
WITHIN 60 NM EITHER SIDE OF THE FRONT. THE REMAINDER OF THE W
ATLC INTO THE CENTRAL ATLC IS UNDER THE INFLUENCE OF A WEAK
SURFACE RIDGE ANCHORED BY A 1023 MB HIGH NEAR 28N48W. THIS
SURFACE RIDGE IS BEING CUT OFF BY A SECOND COLD FRONT THAT
ENTERS THE E/CENTRAL ATLC NEAR 32N34W EXTENDING SW ALONG 26N42W
TO 23N49W THEN CONTINUES AS A STATIONARY FRONT ALONG 21N57W
ACROSS THE VIRGIN ISLANDS INTO THE CARIBBEAN. ISOLATED SHOWERS
ARE POSSIBLE WITHIN 150 NM EITHER SIDE OF THE COLD FRONT WITH
POSSIBLE ISOLATED SHOWERS WITHIN 60 NM EITHER SIDE OF THE
STATIONARY FRONT. THIS FRONT IS SUPPORTED ALOFT BY AN UPPER
LEVEL TROUGH THAT IS N OF 23N BETWEEN 34W-55W. A WEAK 1022 MB
HIGH IS E OF THE FRONT NEAR 25N29W.

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

$$
WALLACE





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