000 AXNT20 KNHC 271039 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT SAT JUN 27 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 1030 UTC. ...SPECIAL FEATURES... ...GALE WARNING CONTINUES IN THE CARIBBEAN SEA... A GALE WARNING FOR MINIMAL GALE FORCE WINDS REMAINS IN EFFECT FOR THE SW CARIBBEAN FROM 11N-17N BETWEEN 70W-79W THROUGH THE AFTERNOON HOURS. THESE CONDITIONS WILL PULSE EVERY EVENING OVER THE NEXT 48 HOURS. THESE WINDS ARE BEING GENERATED DUE TO A TIGHT PRESSURE GRADIENT CREATED BETWEEN THE PERSISTENT STRONG HIGH PRESSURE OVER THE WESTERN ATLANTIC AND THE LOWER PRESSURES OVER SOUTH AMERICA AND THE SW CARIBBEAN SEA. SEE THE LATEST NWS HIGH SEAS FORECAST UNDER AWIPS/WMO HEADERS MIAHSFAT2/FZNT02 KNHC AND THE OFFSHORE FORECAST...MIAOFFNT3/ FZNT23 FOR MORE DETAILS. ...TROPICAL WAVES... A TROPICAL WAVE IS OVER THE FAR EASTERN TROPICAL ATLANTIC WITH AXIS EXTENDING FROM 13N29W TO 03N29W...MOVING W AT 10-15 KT. DESPITE THE FACT THAT THE SSMI TOTAL PRECIPITABLE WATER IMAGERY SHOWS THE WAVE EMBEDDED IN LOW-LEVEL MOISTURE FROM 05N-10N...NO CONVECTION IS OBSERVED ALONG THIS WAVE AS A BROAD SAHARAN AIRMASS PREVAILS ACROSS THE TROPICAL ATLANTIC INHIBITING CONVECTION. A TROPICAL WAVE IS OVER THE CENTRAL TROPICAL ATLANTIC WITH AXIS EXTENDING FROM 14N48W TO 04N48W...MOVING W AT 10-15 KT UNDER THE SOUTHERN PERIPHERY OF A STRONG ATLANTIC HIGH PRESSURE. THE SSMI TOTAL PRECIPITABLE WATER IMAGERY ALSO SHOWS THIS WAVE EMBEDDED IN DEEP LOW-LEVEL MOISTURE AND WITH THE SAHARAN DUST SURGE TO THE N OF 12N...ISOLATED CONVECTION IS OBSERVED E OF THE WAVE AXIS S OF 09N BETWEEN 27W-35W. THIS WAVE IS LIKELY TO AMPLIFY SOME IN LONGITUDINAL SIZE AS IT MOVES FARTHER W DURING THE NEXT 24-48 HOURS. A TROPICAL WAVE CURRENTLY ENTERING THE E CARIBBEAN WITH AXIS EXTENDING FROM 19N62W TO 10N62W...MOVING W AT 10-15 KT. LATEST SATELLITE IMAGERY CONTINUES TO SHOW AN INVERTED-V SHAPE LOW- LEVEL CLOUD PATTERN AND THE SSMI TOTAL PRECIPITABLE WATER IMAGERY SHOWS THIS WAVE EMBEDDED IN AN AREA OF HIGH LOW-LEVEL MOISTURE WHICH IS SUPPORTING ISOLATED CONVECTION ACROSS THE E CARIBBEAN MAINLY E OF 76W. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS ACROSS AFRICA REACHING THE TROPICAL ATLANTIC NEAR 13N17W THROUGH 07N27W. THE ITCZ BEGINS W OF A TROPICAL WAVE NEAR 07N32W TO 06N48W. SCATTERED MODERATE CONVECTION IS OBSERVED FROM 06N-09N BETWEEN 32W-43W. ...DISCUSSION... GULF OF MEXICO... AN UPPER-LEVEL LOW IS CENTERED OVER THE NW GULF NEAR 25N96W AND EXTENDING E OVER MOST OF THE BASIN MAINLY W OF 86W. A WEAK UPPER- LEVEL HIGH IS DEVELOPING OVER THE YUCATAN CHANNEL NEAR 23N87W. TO THE E...ANOTHER UPPER-LEVEL HIGH IS CURRENTLY OVER THE FLORIDA PENINSULA NEAR 27N82W AND PREVAILING ACROSS THE E GULF E OF 86W. THESE FEATURES ARE GENERATING A DIFFLUENT FLOW ACROSS THE S CENTRAL GULF SUPPORTING CLOUDINESS AND ISOLATED CONVECTION S OF 28N BETWEEN 88W-93W. SCATTERED MODERATE CONVECTION IS OBSERVED ACROSS THE BAY OF CAMPECHE S OF 21N BETWEEN 94W-97W. AT THE SURFACE...A 1018 MB HIGH PRESSURE IS CENTERED NEAR 26N88W SUPPORTING A LIGHT TO GENTLE ANTICYCLONIC FLOW ACROSS THE BASIN AND FAIR WEATHER. AN AREA OF GENTLE TO MODERATE WINDS IS DEPICTED IN SCATTEROMETER DATA OVER THE BAY OF CAMPECHE MAINLY S OF 22N BETWEEN 91W-96W. A SIMILAR WEATHER PATTERN IS EXPECTED OVER THE NEXT 24 HOURS. A FRONTAL BOUNDARY WILL APPROACH THE NW GULF WATERS SUPPORTING CONVECTION. CARIBBEAN SEA... A NARROW UPPER-LEVEL RIDGE IS CENTERED OVER THE YUCATAN CHANNEL WHILE AN UPPER-LEVEL LOW EXTENDS ITS TROUGH FROM THE SW ATLANTIC OVER E CUBA AND THE NORTHERN HALF OF THE CARIBBEAN. THIS PATTERN IS SUPPORTING ISOLATED CONVECTION ACROSS THE ADJACENT WATERS S OF CUBA WHILE THE CENTRAL PORTION OF THE BASIN CONTINUES WITH FAIR WEATHER AS A SAHARAN AIRMASS PREVAILS INHIBITING CONVECTION. A TROPICAL WAVE IS ENTERING THE E CARIBBEAN GENERATING ENOUGH INSTABILITY TO SUPPORT ISOLATED CONVECTION ACROSS THIS AREA. FOR MORE INFORMATION PLEASE REFER TO THE SECTION ABOVE. A GALE WARNING CONTINUES IN EFFECT FOR THE WATERS N OF COLOMBIA. FOR MORE INFORMATION...PLEASE REFER TO THE SECTION ABOVE. GENTLE TO MODERATE TRADES ARE DEPICTED IN SCATTEROMETER DATA ACROSS THE REMAINDER OF THE BASIN. OVER THE NEXT 24 HOURS...EXPECT FOR THE TROPICAL WAVE TO CONTINUE MOVING W ACROSS THE E CARIBBEAN INCREASING THE LOW-LEVEL MOISTURE AND HENCE SUPPORTING ISOLATED CONVECTION ACROSS THE GREATER ANTILLES. ...HISPANIOLA... FAIR WEATHER PREVAILS ACROSS THE AREA TONIGHT. A TROPICAL WAVE CURRENTLY JUST OVER THE LEEWARD ISLANDS SHOULD APPROACH HISPANIOLA OVER THE NEXT 24 HOURS INCREASING THE LOW-LEVEL MOISTURE AND HENCE SUPPORTING ISOLATED CONVECTION IN THE AFTERNOON HOURS. ATLANTIC OCEAN... THE BASIN IS UNDER THE INFLUENCE OF A BROAD 1027 MB SURFACE HIGH CENTERED NEAR 29N47W. AT UPPER-LEVELS...A PAIR OF UPPER-LEVEL LOWS CENTERED NEAR 21N75W AND 27N67W ARE SUPPORTING ISOLATED CONVECTION N OF 24N AND W OF 74W AFFECTING THE BAHAMAS AND THE W ATLANTIC WATERS. FAIR WEATHER PREVAILS ACROSS THE REMAINDER OF THE BASIN AS A BROAD SAHARAN AIRMASS CONTINUES ACROSS THE TROPICAL ATLANTIC AS DEPICTED BY THE NOAA/NESDIS AEROSOL PRODUCT AND LATEST VISIBLE SATELLITE IMAGERY. THREE TROPICAL WAVES WERE ANALYZED ACROSS THE BASIN...PLEASE REFER TO THE SECTION ABOVE FOR MORE INFORMATION. OVER THE NEXT 24 HOURS...EXPECT FOR THE SURFACE HIGH AND SAHARAN DUST TO PREVAIL ACROSS THE BASIN WITH FAIR WEATHER. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ ERA