000 AXNT20 KNHC 151046 CCA TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT FRI MAY 15 2015 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. ...SPECIAL FEATURES... A TIGHT PRESSURE GRADIENT BETWEEN HIGH PRESSURE ACROSS THE CENTRAL ATLC AND LOWER PRESSURE ACROSS NORTHWESTERN SOUTH AMERICA IS GENERATING GALE FORCE WINDS WITHIN CLOSE PROXIMITY TO THE COAST OF COLOMBIA FROM 11N TO 14N BETWEEN 72W AND 77W. THE GALE FORCE WINDS ARE EXPECTED TO PERSIST UNTIL 1800 UTC TODAY. SEAS OF 10 TO 14 FEET ARE EXPECTED IN THE WARNED AREA. SEE THE LATEST NWS HIGH SEAS FORECAST UNDER WMO/AWIPS HEADERS MIAHSFAT2/FZNT02 KNHC FOR MORE DETAILS. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 9N13W TO 04N20W TO 03N23W...WHERE THE ITCZ BEGINS AND EXTENDS TO 05N36W. A SURFACE TROUGH IS ALONG A BREAK IN THE ITCZ AND EXTENDS FROM 08N39W TO 04N40W. THE ITCZ RESUMES NEAR 04N42W AND EXTENDS TO THE COAST OF SOUTH AMERICA NEAR 01N50W. WIDELY SCATTERED MODERATE CONVECTION IS FROM 01N TO 07N BETWEEN THE PRIME MERIDIAN AND 31W...AND FROM 04N TO 10N BETWEEN 39W AND 56W. ...DISCUSSION... GULF OF MEXICO... A MIDDLE TO UPPER LEVEL TROUGH EXTENDS ALONG 92W OVER THE CENTRAL GULF...SUPPORTING WIDELY SCATTERED MODERATE CONVECTION FROM 25N TO 30N BETWEEN 84W AND 90W. A SURFACE TROUGH IS OVER THE SOUTHWESTERN GULF FROM 22N91W TO 18N93W. SHOWERS ARE POSSIBLE WITHIN 50 NM OF THE TROUGH AXIS. 10 TO 15 KT E TO SE WINDS COVER THE GULF. OVER THE NEXT 24 HOURS A STORM SYSTEM MOVING EASTWARD ACROSS TEXAS SUPPORT INCREASING CHANCES FOR CONVECTION ACROSS THE NORTHWESTERN GULF LATER TODAY. THE MIDDLE TO UPPER LEVEL TROUGH OVER THE CENTRAL GULF WILL SLIDE SLOWLY EASTWARD TODAY. ONGOING CONVECTION IS EXPECTED ACROSS THE EASTERN HALF OF THE GULF IN THE VICINITY OF THE TROUGH THROUGH TONIGHT. CARIBBEAN SEA... A TIGHT PRESSURE GRADIENT BETWEEN HIGH PRESSURE OVER THE WESTERN ATLC AND LOW PRESSURE OVER NORTHERN COLOMBIA SUPPORTS GALE FORCE WINDS OVER A PORTION OF THE SOUTHWESTERN CARIBBEAN. PLEASE SEE THE SPECIAL FEATURES SECTION FOR MORE DETAILS. ELSEWHERE... MODERATE TO FRESH TRADE WINDS ARE OVER THE CARIBBEAN SEA WITH THE WEAKEST WINDS OVER THE YUCATAN CHANNEL. CONVECTION ASSOCIATED WITH A 1006 MB LOW OVER N COLOMBIA AND THE PACIFIC MONSOON TROUGH OVER COSTA RICA IS SUPPORTING ISOLATED MODERATE CONVECTION S OF 11N BETWEEN 75W AND 84W. ISOLATED MODERATE CONVECTION IS OVER THE GULF OF HONDURAS...SUPPORTED BY AN UPPER TROUGH THAT EXTENDS FROM THE CENTRAL GULF SOUTHWARD OVER THE BELIZE COAST AND INLAND ACROSS CENTRAL AMERICA. CONVECTION IS EXPECTED TO CONTINUE ACROSS THE EXTREME SOUTHWESTERN CARIBBEAN TODAY. DAYTIME THUNDERSTORMS OVER CUBA TODAY WILL MOVE OVER PORTIONS OF THE NW CARIBBEAN TONIGHT. ...HISPANIOLA... EXPECT GENERALLY FAIR CONDITIONS THROUGH THE MORNING WITH SCATTERED SHOWERS AND THUNDERSTORMS POSSIBLE THIS AFTERNOON. CONVECTION WILL DIMINISH OVERNIGHT TONIGHT. EXPECT THIS DAYTIME THUNDERSTORM PATTERN TO REPEAT AGAIN SATURDAY AND SUNDAY. ATLANTIC OCEAN... AN UPPER TROUGH ALONG 60W SUPPORTS A COLD FRONT THAT ENTERS OUR AREA OF DISCUSSION NEAR 32N59W TO 27N65W TO 27N73W WHERE IT TRANSITIONS TO A STATIONARY FRONT THAT CONTINUES TO NORTH FL NEAR 29N81W. ISOLATED MODERATE CONVECTION IS FROM 25N TO 32N BETWEEN 54W AND 60W. SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS ARE POSSIBLE WITHIN 75 NM OF EITHER SIDE OF THE STATIONARY FRONT. A SURFACE TROUGH EXTENDS FROM 26N60W TO 22N63W. NO CONVECTION IS NOTED WITH THIS TROUGH. A 1033 MB HIGH CENTERED NEAR 41N20W DOMINATES THE SUBTROPICAL EASTERN ATLC S OF 32N WITH GENERALLY FAIR WEATHER. OVER THE NEXT 24 HOURS THE COLD FRONT WILL MOVE EAST WITH CONVECTION. THE WESTERN EXTENSION OF THE STATIONARY FRONT THAT REACHES FL WILL DISSIPATE. HOWEVER...MODELS INDICATE THAT CONVECTION WILL REMAIN POSSIBLE FROM THE EAST COAST OF CENTRAL FL TO THE NORTHERN BAHAMAS THROUGH TONIGHT. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ LATTO