000 AXNT20 KNHC 270534 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0530 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 72W-81W THROUGH THE EARLY MORNING 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 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 13N27W TO 04N27W...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 IN THE VICINITY OF 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 14N47W TO 04N47W...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 BETWEEN 09N-11N AND ALONG 45W. 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 MOVING OVER THE WINDWARD ISLANDS WITH AXIS EXTENDING FROM 19N61W TO 09N61W...MOVING W AT 10-15 KT. LATEST SATELLITE IMAGERY CONTINUES TO SHOW AN INVERTED-V SHAPE LOW-LEVEL CLOUD PATTERN WITH THIS WAVE ALTHOUGH LESS DEFINED THAT EARLIER TODAY. THE SSMI TOTAL PRECIPITABLE WATER IMAGERY SHOWS THIS WAVE EMBEDDED IN AN AREA OF HIGH LOW-LEVEL MOISTURE CONTENT BUT ONCE AGAIN THE SAHARAN AIRMASS IS MORE POWERFUL AND CONTINUES INHIBITING ANY SIGNIFICANT CONVECTION. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS ACROSS AFRICA REACHING THE TROPICAL ATLANTIC NEAR 11N16W THROUGH 08N25W. THE ITCZ BEGINS FROM THIS LAST POINT TO 08N27W THEN RESUMES W OF A TROPICAL WAVE NEAR 08N28W TO 07N46W. THE ITCZ BEGINS AGAIN W OF ANOTHER TROPICAL WAVE NEAR 06N47W TO 04N51W. SCATTERED MODERATE CONVECTION IS OBSERVED FROM 06N-09N BETWEEN 32W-40W. ...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 85W. AN UPPER- LEVEL HIGH IS CURRENTLY OVER THE FLORIDA PENINSULA NEAR 28N82W AND PREVAILING ACROSS THE E GULF E OF 85W. UPPER-LEVEL DIFFLUENCE PREVAILS OVER THE SOUTHERN PORTION OF THE BASIN SUPPORTING ISOLATED CONVECTION N OF THE YUCATAN PENINSULA FROM 21N-25N BETWEEN 89W-92W. AT THE SURFACE...A 1018 MB HIGH PRESSURE IS CENTERED NEAR 26N89W 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 21N BETWEEN 91W-94W. A SIMILAR WEATHER PATTERN IS EXPECTED OVER THE NEXT 24 HOURS. 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 INTO THE N CARIBBEAN. THIS PATTERN IS SUPPORTING ISOLATED CONVECTION ACROSS CUBA WHILE THE REMAINDER OF THE BASIN CONTINUES WITH FAIR WEATHER AS A BROAD AREA OF SAHARAN DUST PREVAILS INHIBITING CONVECTION. 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. A TROPICAL WAVE IS CURRENTLY OVER THE WINDWARD ISLANDS WITH NO SIGNIFICANT CONVECTION ASSOCIATED TO IT. FOR MORE INFORMATION PLEASE SEE THE SECTION ABOVE. OVER THE NEXT 24 HOURS...EXPECT FOR THE TROPICAL WAVE TO MOVE 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 WINDWARD ISLANDS SHOULD APPROACH HISPANIOLA OVER THE NEXT 24 HOURS INCREASING THE LOW-LEVEL MOISTURE AND HENCE SUPPORTING ISOLATED CONVECTION IN THE AFTERNOON HOURS DUE TO DAYTIME HEATING AND OROGRAPHIC LIFTING. ATLANTIC OCEAN... THE BASIN IS UNDER THE INFLUENCE OF A BROAD 1030 MB SURFACE HIGH CENTERED NEAR 29N49W. AT UPPER-LEVELS...A PAIR OF UPPER-LEVEL LOWS CENTERED NEAR 21N75W AND 26N69W ARE SUPPORTING ISOLATED CONVECTION N OF 22N AND W OF 75W AFFECTING THE BAHAMAS AND PORTIONS OF CUBA. 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