000 AXNT20 KNHC 110545 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 AM EDT MON MAY 11 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0515 UTC. ...GALE WARNING FOR SW CARIBBEAN... A GALE WARNING IS IN EFFECT FROM 11N TO 13.5N BETWEEN 72W AND 76W DUE TO A TIGHT PRESSURE GRADIENT BETWEEN HIGH PRESSURE OVER THE ATLC AND LOW PRESSURE OVER NORTHERN COLOMBIA. SEAS ARE EXPECTED TO BUILD TO 10 TO 15 FT WITH THE STRONGEST WINDS. WINDS ARE FORECAST TO CONTINUE NEAR MINIMAL GALE FORCE THROUGH THE EARLY MORNING HOURS BEFORE DROPPING BELOW GALE FORCE DURING THE DAY MONDAY. WINDS WILL PULSE BACK TO MINIMAL GALE FORCE MONDAY NIGHT AND AGAIN ON TUESDAY NIGHT. PLEASE SEE THE HIGH SEAS FORECAST UNDER WMO/AWIPS HEADERS MIAHSFAT2/FZNT02 KNHC FOR MORE DETAILS. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS ACROSS AFRICA REACHING THE TROPICAL ATLANTIC NEAR 20N16W TO 13N19W TO 07N23W WHERE THE ITCZ BEGINS AND CONTINUES THROUGH 05N35W TO 01N50W. ISOLATED MODERATE CONVECTION IS FROM 03N TO 07N BETWEEN 18W AND 50W. ...DISCUSSION... GULF OF MEXICO... A RIDGE AXIS EXTENDS ACROSS THE WESTERN ATLC AND FLORIDA AND ACROSS THE NORTHERN GULF. A 1019 MB STATIONARY HIGH IS SITUATED ALONG THE RIDGE AXIS OVER THE NORTHEASTERN GULF NEAR 29N85W. LIGHT AND VARIABLE WINDS ARE WITHIN 50 NM OF THE HIGH. SOUTHEAST WINDS OF 10 TO 15 KT ARE OVER THE EASTERN GULF EAST OF 88W AWAY FROM THE HIGH CENTER. EASTERLY TO SOUTHEASTERLY WINDS OF 15 TO 20 KT ARE OVER THE REMAINDER OF THE GULF. CURRENTLY THE GULF IS FREE OF CONVECTION. HOWEVER...A TROUGH OVER THE CENTRAL US WILL MOVE EASTWARD AND WILL SUPPORT CONVECTION OVER THE NORTHWESTERN GULF LATER TODAY THROUGH TUESDAY MORNING. A SURFACE TROUGH WILL DEVELOP EACH AFTERNOON ACROSS THE YUCATAN PENINSULA AND SHIFT WEST-NORTHWEST ACROSS THE SOUTHWEST GULF DURING THE EVENING AND OVERNIGHT HOURS...ENHANCING THE WINDS AND SEAS OVER THESE LOCATIONS. CARIBBEAN SEA... BROAD RIDGING THAT PREVAILS ACROSS THE CENTRAL AND WESTERN ATLC EXTENDS SOUTHWEST ACROSS THE NORTHERN CARIBBEAN. LOW PRESSURE IS OVER NORTHERN COLOMBIA. A TIGHT PRESSURE GRADIENT BETWEEN THESE TWO SURFACE FEATURES SUPPORTS NEAR GALE FORCE WINDS OVER A PORTION OF THE SOUTHWESTERN CARIBBEAN. SEE THE SPECIAL FEATURES SECTION FOR MORE DETAILS. AN UPPER LEVEL TROUGH EXTENDING FROM THE BAHAMAS TO JAMAICA TO NEAR 12N80W SUPPORTS ISOLATED THUNDERSTORMS FROM 18N TO 22N BETWEEN 72W AND 82W. SCATTERED MODERATE CONVECTION IS FROM THE COAST OF PANAMA TO 11N BETWEEN 80W AND 84W...AND IS ASSOCIATED WITH INTERACTION BETWEEN A SURFACE TROUGH OVER THE EASTERN PACIFIC AND THE UPPER TROUGH OVER THE WESTERN CARIBBEAN. THE UPPER TROUGH WILL WEAKEN OVER THE NEXT 24 HOURS. CONVECTION IS FORECAST TO CONTINUE OVER THE SOUTHWESTERN CARIBBEAN THROUGH TONIGHT. ...HISPANIOLA... AN UPPER LEVEL TROUGH WEST OF THE ISLAND IS INTERACTING WITH A MOIST AIRMASS TO SUPPORT SCATTERED MAINLY DAYTIME SHOWERS AND THUNDERSTORMS OVER THE ISLAND. THIS PATTERN WILL CONTINUE TODAY WITH A DECREASE IN COVERAGE BY TUESDAY AS THE UPPER TROUGH WEAKENS. ATLANTIC OCEAN... AN UPPER TROUGH EXTENDING FROM THE CENTRAL BAHAMAS TO THE WESTERN CARIBBEAN SUPPORTS ISOLATED THUNDERSTORMS FROM CUBA NORTH TO 25N BETWEEN 71W AND 80W. BROAD RIDGING ANCHORED BY A 1032 MB HIGH IS CENTERED OVER THE CENTRAL ATLC NEAR 34N54W. THIS HIGH SUPPORTS ANTICYCLONIC FLOW AND GENERALLY FAIR WEATHER ACROSS MUCH OF THE CENTRAL AND WESTERN ATLC SOUTH OF 32N. FARTHER EAST...A LOW PRESSURE SYSTEM NEAR 34N32W SUPPORTS A COLD FRONT THAT ENTERS OUR AREA OF DISCUSSION NEAR 32N30W AND EXTENDS TO 25N35W TO 23N46W TO 26N56W. NO DEEP CONVECTION IS NOTED WITH THIS FRONT. NORTHWESTERLY WINDS OF 25 TO 30 KT ARE FROM 27N TO 32N BETWEEN 31W AND 39W. THE COLD FRONT WILL CONTINUE EASTWARD OVER THE NEXT 24 HOURS. LITTLE CHANGE IS EXPECTED ELSEWHERE. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ LATTO