000 AXNT20 KNHC 111010 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1015 UTC. ...GALE WARNING FOR SW CARIBBEAN... A GALE WARNING IS IN EFFECT FROM 11N TO 13.5N BETWEEN 72W AND 76.5W 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 MORNING HOURS BEFORE DROPPING BELOW GALE FORCE DURING LATE THIS AFTERNOON. WINDS WILL PULSE BACK TO MINIMAL GALE FORCE LATE TONIGHT 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 11N15W TO 06N22W WHERE THE ITCZ BEGINS AND CONTINUES THROUGH 05N35W TO 02N51W. ISOLATED MODERATE CONVECTION IS WITHIN 75 NM OF THE ITCZ AXIS. ...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 29N84W. 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 86W 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 12N83W SUPPORTS ISOLATED THUNDERSTORMS FROM 18N TO 22N BETWEEN 72W AND 84W. SCATTERED MODERATE CONVECTION IS FROM THE COAST OF PANAMA TO 12N BETWEEN 80W AND 85W...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... CURRENTLY...ISOLATED SHOWERS ARE OVER THE ISLAND. AN UPPER LEVEL TROUGH WEST OF THE ISLAND IS INTERACTING WITH A MOIST AIRMASS WHICH WILL SUPPORT SCATTERED THUNDERSTORMS OVER THE ISLAND THIS AFTERNOON AND EVENING. A DECREASE IN COVERAGE IN SHOWERS AND THUNDERSTORMS CAN BE EXPECTED 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 72W AND 79W. BROAD RIDGING ANCHORED BY A 1029 MB HIGH IS CENTERED OVER THE CENTRAL ATLC NEAR 33N54W. 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 34N28W SUPPORTS A COLD FRONT THAT ENTERS OUR AREA OF DISCUSSION NEAR 32N28W AND EXTENDS TO 25N33W TO 23N40W TO 23N52W. NO DEEP CONVECTION IS NOTED WITH THIS FRONT. NORTHWESTERLY WINDS OF 25 TO 30 KT ARE FROM 27N TO 32N BETWEEN 28W AND 40W. 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