000
AXNT20 KNHC 041043
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
805 AM EDT FRI MAY 04 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1015 UTC.

...ITCZ/MONSOON TROUGH...

THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 12N16W TO 
TO 05N19W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 
05N19W TO 02N36W TO 02N51W. ISOLATED MODERATE TO STRONG 
CONVECTION IS FROM 03N-11N BETWEEN 02W-06W.

...DISCUSSION...

GULF OF MEXICO...
AN UPPER LEVEL SHORTWAVE TROUGH IS OVER THE SE CONUS THIS 
MORNING WITH AXIS EXTENDING INTO THE NE GULF ALONG 30N84W TO 
24N83W. WHILE NO DISCERNIBLE SURFACE FEATURE IS NOTED OVER THE 
EASTERN GULF WATERS...MOSAIC DOPPLER RADAR INDICATES WIDELY 
SCATTERED SHOWERS ARE OCCURRING N OF 25N E OF 85W. OTHERWISE... 
THE REMAINDER OF THE GULF BASIN IS UNDER THE INFLUENCE OF STABLE 
WEST TO NORTHWEST FLOW ALOFT DUE TO AN UPPER LEVEL RIDGE WITH 
AXIS ALONG 95W. HIGH LEVEL MOISTURE AND CLOUDINESS CONTINUES TO 
ADVECT EASTWARD OVER FAR PORTIONS OF THE WESTERN GULF DUE TO 
EARLIER OVERNIGHT DIMINISHED CONVECTION OVER INLAND EASTERN 
MEXICO. MOSTLY EAST TO SOUTHEAST WINDS ARE OBSERVED IN THE RANGE 
OF 10 TO 15 KT AS HIGH PRESSURE IS FORECAST TO BUILD WESTWARD 
AND ANCHOR ITSELF OVER THE FLORIDA PENINSULA FRIDAY AND THEN 
SLIDE FARTHER WEST INTO THE EASTERN GULF WATERS OVER THE WEEKEND.

CARIBBEAN SEA...
WEST TO SOUTHWESTERLY UPPER LEVEL FLOW DOMINATES ACROSS THE 
CARIBBEAN THIS MORNING WITH MOSTLY MIDDLE TO UPPER LEVEL 
MOISTURE REMAINING E OF 74W AS AN UPPER LEVEL TROUGH WITH AXIS 
FROM 23N71W TO 15N79W CONTINUES TO PROVIDE AMPLE MIDDLE TO UPPER 
LEVEL DIFFLUENCE ALOFT. LOW-LEVEL MOISTURE PRESENT EAST OF THIS 
TROUGH AXIS OVER THE EASTER CARIBBEAN COUPLED WITH A SURFACE 
TROUGH ANALYZED FROM 22N62W TO 17N69W ARE PROVIDING FOCUS FOR 
SCATTERED SHOWERS AND ISOLATED TSTMS E OF 66W...INCLUDING PUERTO 
RICO...AND THE LESSER ANTILLES. GLOBAL MODEL GUIDANCE HAS 
CONTINUED TO SUGGEST THAT THE SURFACE TROUGHING WILL REMAIN 
NEARLY STATIONARY OVER THE EASTERN CARIBBEAN THROUGH THE WEEKEND 
INCREASING THE PROBABILITY OF SCATTERED SHOWERS AND TSTMS 
THROUGH THE WEEKEND E OF 75W. OTHERWISE...THE REMAINDER OF THE 
CARIBBEAN IS EXPERIENCING MOSTLY CLEAR SKIES AND FAIR WEATHER 
CONDITIONS THAT ARE EXPECTED TO CONTINUE THROUGH THE DAY ON 
FRIDAY.

ATLANTIC OCEAN...
MIDDLE TO UPPER LEVEL RIDGING IS ANCHORED OVER THE EASTERN U.S. 
SEABOARD AND THIS MANIFESTS ITSELF AT THE SURFACE WITH A 1020 MB 
HIGH CENTERED NEAR 30N77W. CLEAR SKIES ARE NOTED OVER THE REGION 
N OF 20N W OF 70W THIS MORNING. FARTHER EAST...A MIDDLE TO UPPER 
LEVEL TROUGH HAS MOVED S OF 30N NEAR 66W AS NOTED ON WATER VAPOR 
IMAGERY AND EXTENDS AN AXIS FROM 30N63W TO 25N71 TO OVER THE 
WINDWARD PASSAGE NEAR 20N74W. THIS TROUGHING SUPPORTS A COLD 
FRONT ANALYZED ALONG 30N BETWEEN 54W-70W AND IS GENERATING 
ISOLATED SHOWERS WITHIN 120 NM EITHER SIDE OF THE COLD FRONT. 
THE UPPER LEVEL TROUGH IS ALSO THE DRIVING FORCE BEHIND 
SCATTERED SHOWERS AND ISOLATED TSTMS OCCURRING FROM 13N-23N 
BETWEEN 55W-70W...NE OF THE EASTERN CARIBBEAN SEA. THE REMAINDER 
OF THE EASTERN ATLC IS UNDER THE INFLUENCE OF A SURFACE RIDGE 
ANCHORED BY A 1022 MB HIGH CENTERED NEAR 26N28W.

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

$$
HUFFMAN