000 AXNT20 KNHC 072357 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT MON MAY 07 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 2315 UTC. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 09N13W TO 05N19W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 05N19W TO 03N27W TO 02N40W TO 03N45W TO 03N51W. ISOLATED MODERATE TO STRONG CONVECTION IS FROM 05N-08N BETWEEN 08W-13W. ISOLATED MODERATE CONVECTION IS FROM 01N-06N BETWEEN 19W-34W. ...DISCUSSION... GULF OF MEXICO... DRY WESTERLY FLOW ALOFT IS NOTED OVER THE GULF THIS EVENING AS CONDITIONS REMAIN GENERALLY FAIR AT THE SURFACE...HOWEVER AN UPPER LEVEL SHORTWAVE TROUGH IS NOTED ON WATER VAPOR IMAGERY OVER LOUISIANA THAT EXTENDS A WEAK MIDDLE TO UPPER LEVEL TROUGH AXIS SE OVER THE NE GULF TO NEAR 28N85W. A SURFACE TROUGH IS ANALYZED FROM THE TAMPA BAY REGION NORTHWESTWARD TO THE MISSISSIPPI DELTA REGION NEAR 29N90W AND IS PROVIDING FOCUS FOR ISOLATED SHOWERS OCCURRING FROM 25N-28N BETWEEN 83W-86W...AND N OF 28N BETWEEN 89W-92W. THIS WEAK SURFACE TROUGHING IS FORECAST TO REMAIN NEARLY STATIONARY OVER THE NEXT 24 TO 36 HOURS AND BECOME ABSORBED BY THE NEXT FRONTAL BOUNDARY TO MOVE INTO THE NW GULF THEN STALL ACROSS THE NORTHERN GULF WATERS WEDNESDAY. THE FRONT WILL QUICKLY SWEEP EAST OF THE REGION AND MOVE INTO THE SW NORTH ATLC ON THURSDAY. CARIBBEAN SEA... DRY WESTERLY FLOW ALOFT IS NOTED ON WATER VAPOR IMAGERY THIS EVENING OVER MUCH OF THE CARIBBEAN SEA N OF 13N. THE MOST DISCERNIBLE AREA OF MIDDLE TO UPPER LEVEL MOISTURE IS LOCATED OVER THE FAR EASTERN CARIBBEAN E OF 64W AS UPPER LEVEL DIFFLUENCE COUPLED WITH A SURFACE TROUGH ANALYZED FROM 18N63W TO 14N68W IS PROVIDING FOCUS FOR SCATTERED SHOWERS AND ISOLATED TSTMS SE OF THE SURFACE TROUGH AXIS...INCLUDING THE LESSER ANTILLES. SCATTERED SHOWERS AND ISOLATED TSTMS ARE ALSO OCCURRING S OF 13N AS AN UPPER LEVEL RIDGE AXIS EXTENDS ALONG 10N. THE EASTERN PACIFIC MONSOON TROUGH AXIS EXTENDS FROM COSTA RICA TO EASTERN PANAMA NEAR 09N77W. ATLANTIC OCEAN... UPPER LEVEL TROUGHING IS OVER THE CENTRAL ATLC REMAINING LARGELY N OF 30N BETWEEN 40W-60W. A COLD FRONT IS SUPPORTED BY THIS UPPER LEVEL FEATURE AND EXTENDS S-SW INTO THE DISCUSSION AREA NEAR 32N43W TO 27N50W THEN MEANDERING WESTWARD TO A 1009 MB LOW CENTERED NEAR 28N56W. A WEAK FRONTAL TROUGH THEN CONTINUES AS A STATIONARY FRONT TO A 1011 MB LOW CENTERED NEAR 29N71W. A WEAK COLD FRONT THEN EXTENDS WESTWARD TO THE FLORIDA PENINSULA ALONG 28N74W TO 29N80W. ISOLATED SHOWERS ARE OCCURRING WITHIN 120 NM EITHER SIDE OF THIS ENTIRE FRONTAL BOUNDARY WITH A FEW ADDITIONAL ISOLATED TSTMS OCCURRING FROM 27N-32N W OF 77W... INCLUDING PORTIONS OF THE NORTHERN FLORIDA PENINSULA. WITH THE MAIN UPPER LEVEL TROUGH AXIS EXTENDING FROM 30N50W TO 19N66W...A SURFACE TROUGH IS ANALYZED FROM 21N58W TO 18N63W AND INTO THE EASTERN CARIBBEAN SEA. ANOTHER SURFACE TROUGH IS LOCATED SE OF THE AFOREMENTIONED COLD FRONT ACROSS THE CENTRAL ATLC FROM 27N42W TO 20N48W...ALL LIKELY SUPPORTED ALOFT BY THIS UPPER LEVEL TROUGHING. A WIDE 540 NM SWATH OF MIDDLE TO UPPER LEVEL MOISTURE EXTENDS FROM THE EASTERN CARIBBEAN SEA NORTHEASTWARD TO 31N27W AND ALONG WITH LOW-LEVEL MOISTURE CONVERGENCE...OVERCAST SKIES WITH WIDELY SCATTERED SHOWERS EXTEND OVER MUCH OF THIS AREA. THE REMAINDER OF THE EASTERN ATLC IS UNDER THE INFLUENCE OF A SURFACE RIDGE ANCHORED BY A 1020 MB HIGH CENTERED WEST OF THE CANARY ISLANDS NEAR 29N20W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ HUFFMAN