[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 170535
TWDAT

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
105 AM EST SUN JAN 17 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 0530 UTC.

...THE ITCZ...

THE ITCZ AXIS IS ANALYZED FROM WEST AFRICA NEAR THE SOUTHERN
COAST OF LIBERIA AT 4N9W CONTINUING WESTWARD ALONG 3N20W 3N30W
3N40W TO NORTHEAST BRAZIL NEAR 1N50W. NO SIGNIFICANT CONVECTION
IS OBSERVED AT THIS TIME.

...DISCUSSION...

THE GULF OF MEXICO...
A COLD FRONT IS GETTING READY TO HIT THE WESTERN FLORIDA
PENINSULA OVER THE NEXT 6 TO 12 HOURS. THIS COLD FRONT IS
ANALYZED CROSSING THE FLORIDA PANHANDLE AND CONTINUES TO EXTEND
SOUTH ALONG 29N85W 26N85W 24N84W ENTERING THE YUCATAN CHANNEL
THROUGH 21N85W. WIDELY SCATTERED MODERATE TO STRONG CONVECTION
IS AHEAD OF THIS SYSTEM. DOPPLER RADAR IMAGERY SHOWS MODERATE
SHOWERS OVER MOST OF THE FLORIDA PENINSULA NORTH OF 26N. A LINE
OF HEAVY SHOWERS IS PASSING OVER THE STRAIGHTS OF FLORIDA AND
WILL IMPACT THE FLORIDA KEYS AND SOUTHERN FLORIDA OVER THE NEXT
6 TO 9 HOURS. SATELLITE WATER VAPOR IMAGERY SHOWS STRONG
SUBSIDENCE OF AIR BEHIND THE SYSTEM COVERING MOST OF THE WESTERN
AND CENTRAL BASIN. THUS...THE SURFACE PRESSURE GRADIENT OVER THE
GULF OF MEXICO HAS LOOSEN PRODUCING 10 TO 20 KT WEST WINDS OVER
MOST OF THE BASIN. SURFACE OBSERVATION OVER THE FLORIDA
PENINSULA SHOW SOUTH WINDS 15 TO 25 KT. IN 24 HOURS THIS FRONT
WILL CONTINUE TO MOVE EASTWARD CROSSING THE FLORIDA PENINSULA
AND ENTERING THE WESTERN ATLANTIC OCEAN WITH CONVECTION AHEAD OF
IT...WHILE A SURFACE HIGH PRESSURE ENTERS THE WESTERN GULF
BRINGING CALM WEATHER TO THE REGION.

THE CARIBBEAN SEA...
SATELLITE WATER VAPOR SHOWS STRONG SUBSIDENCE OF AIR OVER THE
ENTIRE CARIBBEAN SEA. THIS UPPER LEVEL FEATURE IS SUPPRESSING
DEEP CONVECTION OVER MOST OF THE AREA. ONLY WEAK CONVECTION IS
DEVELOPING OVER THE NORTHERN SEA BASIN AS THE TAIL END OF A
TROUGH LINGERS NORTH OF THE DOMINICAN REPUBLIC...PUERTO
RICO...AND THE LEEWARD ISLANDS. DOPPLER RADAR IMAGERY SHOWS
FEWER SCATTER SHOWERS OVER THE ISLAND OF PUERTO RICO...COMPARED
TO 24 HOUR AGO WHEN THE FRONTAL SYSTEM WAS OVER THE MENTIONED
ISLANDS. THESE SHOWERS ARE MOVING EASTWARD AT ABOUT 15 KT. THE
TAIL END OF A COLD FRONT IS ENTERING THE NORTHWEST BASIN. THIS
FRONT IS ANALYZED ALONG 22N85W 20N86W 18N87W. A LINE OF SHOWERS
IS SEEN 50 NM AHEAD OF THE FRONT. SHIP AND BUOY OBSERVATIONS
SHOW SOUTH-SOUTHEAST WINDS AHEAD OF THE FRONT TO 83W. EASTERLY
WINDS 15 TO 20 KT ARE OBSERVED ELSEWHERE ACROSS THE BASIN. A
TIGHT SURFACE PRESSURE GRADIENT IS GENERATING GALE FORCE WINDS
WITHIN 200 NM OFF THE COAST OF NORTH COLOMBIA...FROM 11N TO 14N
BETWEEN 74W AND 77W...EXPECTED TO CONTINUE OVER THE NEXT 12 TO
18 HOURS.

THE ATLANTIC OCEAN...

HIGH PRESSURE IS OVER MOST OF THE WESTERN AND CENTRAL
ATLANTIC...SUPPORTED BY A LARGE UPPER LEVEL RIDGE WEST OF 50W.
THEREFORE...FAIR WEATHER IS OBSERVED NORTH OF 20N WEST OF 40W.
NEVERTHELESS...WEAK TO MODERATE CONVECTION IS ENTERING THE
WESTERN ATLANTIC OCEAN WITH GALE FORCE WINDS EXPECTED TO DEVELOP
IN THIS REGION NORTH OF 29N WEST OF 77W OVER THE NEXT 6 TO 9
HOURS AS SURFACE PRESSURE GRADIENT TIGHTENS IN THIS REGION. A
SURFACE LOW IS ANALYZED OVER THE EASTERN ATLANTIC NEAR 35N23W. A
COLD FRONT EXTENDS SOUTHWEST FROM THE LOW CENTER ENTERING THE
DISCUSSION AREA THROUGH 32N24W AND CONTINUES ALONG 24N30W 20N38W
17N50W CONTINUING WESTWARD AS A STATIONARY FRONT ENTERING THE
EASTERN CARIBBEAN THROUGH 17N62W. WEAK CONVECTION IS FOUND
WITHIN 80 NM ON EITHER SIDE OF THE FRONT. THIS FRONT WILL
CONTINUE TO SLOWLY MOVE EASTWARD INTO THE WESTERN AFRICA COAST
WITH DEBILITATED CONVECTION IN IT.


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

$$

GARCIA


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