[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 060001
TWDAT

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
105 PM EST THU JAN 05 2012

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...WEATHER OBSERVATIONS...RADAR...AND METEOROLOGICAL
ANALYSIS.

BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
2345 UTC.

...ITCZ/MONSOON TROUGH...

MOST OF THE MONSOON TROUGH REMAINS INLAND OVER AFRICA. ONLY A
SMALL PORTION OF IT EXTENDS FROM THE COAST OF LIBERIA NEAR 5N10W
TO ABOUT 3N13W. THE ITCZ EXTENDS WESTWARD FROM THIS POINT ALONG
4N30W 6N46W TO THE COAST OF BRAZIL NEAR 2N49W. WIDELY SCATTERED
WEAK TO ISOLATED MODERATE CONVECTION IS WITHIN 170 NM ON EITHER
SIDE OF THE ITCZ AXIS W OF 37W.

...DISCUSSION...

GULF OF MEXICO...
WATER VAPOR IMAGERY SHOWS WESTERLY FLOW CARRYING DRY AIR AND
MODERATE SUBSIDENCE ALOFT ACROSS THE GULF THIS EVENING. THIS
UPPER LEVEL ENVIRONMENT SUPPORTS A 1028 MB HIGH CENTERED NEAR
27N89W. MARINE OBSERVATIONS INDICATE LIGHT AND VARIABLE WINDS IN
THE VICINITY OF THE HIGH CENTER...WHILE ANTICYCLONIC FLOW
ELSEWHERE ACROSS THE AREA. A TEMPERATURE GRADIENT OF ABOUT 15-20
DEGREES WAS OBSERVED BETWEEN LAND AND SEA EARLIER TODAY ALONG
THE TEXAS COAST AND NRN GULF COAST STATES TO THE WRN FLORIDA
PANHANDLE. THIS GRADIENT HELPED TO MAINTAIN A WEAK STATIONARY
FRONTAL BOUNDARY WITHIN 10 NM INLAND...GENERATING A FEW POSSIBLE
ISOLATED SHOWERS IN THE VICINITY OF THE BOUNDARY. OTHERWISE...
FAIR WEATHER CONDITIONS ARE ELSEWHERE ACROSS THE AREA. THE
CURRENT ANTICYCLONIC FLOW WILL BECOME MORE ESE TO RETURN FLOW AS
THE HIGH PRESSURE CENTER DRIFTS E TO CENTRAL FLORIDA OVER THE
NEXT 24 HOURS. ANOTHER ROUND OF CONVECTIVE WEATHER IS EXPECTED
STARTING SUNDAY...AS THE NEXT COLD FRONT IS FORECAST TO ENTER
THE NW BASIN.

CARIBBEAN SEA...
THE SRN EXTENSION OF A STATIONARY FRONT EXTENDING SW ACROSS THE
ATLC ENTERS THE CARIBBEAN THROUGH THE MONA PASSAGE ALONG 18N68W
BECOMING WEAK NEAR 16N70W TO THE COAST OF PANAMA ALONG 14N78W TO
NEAR 9N82W. AN EARLIER ASCAT PASS INDICATED NORTHERLY WINDS AND
NE WINDS CONVERGING ALONG THE BOUNDARY WITH CONSIDERABLE LOW
LEVEL MOISTURE AVAILABLE IS GENERATING AN AREA OF SCATTERED WEAK
SHOWERS WITHIN 150 NM ON WRN SIDE OF THE BOUNDARY. OTHERWISE...
DRY AIR AND STRONG SUBSIDENCE IN THE UPPER LEVELS REMAIN
ELSEWHERE ACROSS THE BASIN. MOST OF THE RAIN ACTIVITY IS
EXPECTED TO SHIFT WESTWARD INTO CENTRAL AMERICA WITH SOME OF IT
LINGERING NEAR THE COAST OF ERN HONDURAS...NICARAGUA...AND COSTA
RICA OVER THE NEXT 24 HRS.

ATLANTIC OCEAN...
A BROAD UPPER LEVEL TROUGH COVERS THE WRN N ATLC W OF 60W. THE
FLOW AROUND THE UPPER TROUGH IS DRIVING AN UPPER LEVEL LONGWAVE
OFF THE SE CONUS SEABOARD...SUPPORTING A SURFACE TROUGH THAT
EXTENDS INTO OUR DISCUSSION AREA ALONG 32N72W TO NEAR THE COAST
OF FLORIDA AROUND 28N79W. THE CONVECTION ASSOCIATED TO THIS
SYSTEM REMAINS N OF THE DISCUSSION AREA. HOWEVER...AS THE
SURFACE TROUGH CONTINUES TO TRACK EASTWARD...SOME LIMITED WEAK
CONVECTION COULD ENTER THE AREA N OF 28N DURING THE NEXT 24
HOURS. FARTHER AHEAD...A STATIONARY FRONT EXTENDS SW ACROSS THE
N CENTRAL ATLC ENTERING THE REGION ALONG 32N52W INTO THE
CARIBBEAN BASIN ACROSS THE MONA PASSAGE. THIS SURFACE FEATURE
HAS LOST ITS UPPER LEVEL SUPPORT WITH A FEW SCATTERED SHOWERS
REMAINING WITHIN 80 NM E OF THE BOUNDARY N OF 25N. SIMILAR
CONDITIONS ARE EXPECTED TO CONTINUE WITH THIS BOUNDARY OVER THE
NEXT 24 HOURS. OTHERWISE... BROAD SURFACE RIDGING AROUND A
STRONG 1038 MB HIGH CENTERED OFF THE COAST OF PORTUGAL NEAR
42N16W IS KEEPING FAIR WEATHER CONDITIONS ACROSS THE REMAINDER
OF THE DISCUSSION AREA THIS EVENING.

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

$$

GARCIA



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