000 AXNT20 KNHC 260001 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT THU JUN 25 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2345 UTC. ...SPECIAL FEATURES... MINIMAL GALE-FORCE WINDS ARE EXPECTED TO RAMP AGAIN SHORTLY IN THE COASTAL AND OFFSHORE WATERS OF COLOMBIA...FROM 11.5N TO 16N BETWEEN 70W AND 80W...THE WINDS ARE FORECAST TO PULSE AROUND MARGINAL GALE-FORCE FOR THE NEXT 48 HOURS. WAVE HEIGHTS ARE FORECAST TO RANGE FROM 11 FEET TO 17 FEET DURING THE NEXT 48 HOURS. PLEASE READ THE HIGH SEAS FORECAST... MIAHSFAT2/FZNT02 KNHC...AND THE OFFSHORE FORECAST...MIAOFFNT3/ FZNT23 KNHC...FOR MORE DETAILS. ...TROPICAL WAVES... LOW AMPLITUDE TROPICAL WAVE IS ALONG 38W/39W FROM 13N SOUTHWARD...MOVING WESTWARD 20 KNOTS. SCATTERED MODERATE TO ISOLATED STRONG CONVECTION WAS NOTED AT THE INTERSECTION OF THE WAVE AXIS AND THE ITCZ FROM 5N TO 8N BETWEEN 36W AND 42W. TROPICAL WAVE IS ALONG 55W FROM 20N SOUTHWARD...MOVING WESTWARD AT 20 KNOTS. LAST VISIBLE SATELLITE IMAGES DEPICTED AN INVERTED- V SHAPE IN THE LOW LEVEL CLOUDINESS ACCOMPANYING THE WAVE. SCATTERED LOW TOPPED SHOWERS ARE POSSIBLE IN THE ASSOCIATED CLOUDINESS. A CARIBBEAN SEA TROPICAL WAVE IS ALONG 80W/81W FROM 17N SOUTHWARD. THE WAVE IS MOVING WESTWARD 10 TO 15 KNOTS. NO SIGNIFICANT DEEP CONVECTION IS ASSOCIATED WITH THE WAVE. A TROPICAL WAVE IS MOVING THROUGH THE FAR SOUTHWESTERN CORNER OF THE GULF OF MEXICO. IT IS MOVING BENEATH THE AREA OF THE MID TO UPPER LEVEL CYCLONIC FLOW THAT IS ACCOMPANYING THE CYCLONIC CIRCULATION NEAR 23N94W. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH PASSES THROUGH COASTAL SECTIONS OF SENEGAL NEAR 13N17W TO 10N22W. THE ITCZ CONTINUES FROM 10N22W THROUGH 9N32W 5N43W TO 6N53W NEAR THE COAST OF FRENCH GUIANA. NO SIGNIFICANT CONVECTION WAS NOTED OUTSIDE THE AREA NOTED IN ASSOCIATION WITH THE TROPICAL WAVE ALONG 38W/39W ABOVE. ...DISCUSSION... ...GULF OF MEXICO... LARGE-SCALE MID-TO UPPER LEVEL CYCLONIC FLOW COVERS THE GULF OF MEXICO S OF 28N W OF 85W ANCHORED BY A CYCLONIC CIRCULATION NEAR 23N94W. ANTICYCLONIC FLOW PREVAILED OVER THE NORTHEAST GULF S OF A NARROW RIDGE AXIS ALONG THE IMMEDIATE GULF COAST. AT THE SURFACE A 1021 MB HIGH CENTER WAS NEAR 28N86W. A TROUGH EXTENDED FROM NEAR PENSACOLA FLORIDA TO 28N90W TO THE COAST OF LOUISIANA NEAR LAKE CHARLES. SURFACE OBSERVATIONS AND SCATTEROMETER DATA INDICATED VERY LIGHT WINDS OF 5 TO 10 KNOTS MOST AREAS. SCATTERED MODERATE TO STRONG CONVECTION WAS CONFINED TO NEAR THE WEST COAST OF FLORIDA...INLAND OVER THE CENTRAL GULF COAST AND OVER THE NORTHWEST YUCATAN. ISOLATED CLUSTERS OF CONVECTION WAS NOTED OVER THE BAY OF CAMPECHE. PATCHES OF CUMULIFORM CLOUDS WERE NOTED OVER THE REMAINDER OF THE GULF. ...CARIBBEAN SEA... MID-TO UPPER LEVEL WEST-NORTHWEST FLOW PREVAILED OVER THE FAR NORTHERN CARIBBEAN E OF 80W COURTESY OF AN ELONGATED CYCLONIC CIRCULATION OVER THE SW N ATLANTIC NEAR THE BAHAMAS. THE CYCLONIC FLOW ASSOCIATED WITH THE CIRCULATION OVER THE GULF HAS MOVED W OF THE AREA AND WAS REPLACED BY A NARROW SHORTWAVE RIDGE ALONG 83W. THE FLOW BECOMES WESTERLY OR SOUTHWESTERLY OVER THE REMAINDER OF THE CARIBBEAN SEA WITH WATER VAPOR IMAGERY SHOWING SIGNIFICANT SUBSIDENCE IN THE AREA. VERY DIFFLUENT FLOW WAS NOTED OVER THE FAR W CARIBBEAN AND THE GULF OF HONDURAS WHICH COUPLED WITH OROGRAPHIC LIFT MAINTAINED SCATTERED MODERATE TO STRONG CONVECTION OVER NICARAGUA...HONDURAS...BELIZE AND MOST OF THE YUCATAN PENINSULA. ADDITIONAL AREAS OF STRING CONVECTION WERE NOTED OVER PORTIONS OF CENTRAL AND EASTERN CUBA. AT THE SURFACE MODERATE TO FRESH EASTERLY WINDS WERE NOTED OVER THE AREA N OF 17N WITH STRONG TO NEAR GALE FORCE WINDS NOTED OVER THE AREA S OF 17N BETWEEN 70W AND 80W. A GALE WARNING IS IN EFFECT FOR THE COASTAL AND OFFSHORE WATERS OF COLOMBIA...FROM 11.5N TO 16N BETWEEN 70W AND 80W. ...HISPANIOLA... MIDDLE LEVEL TO UPPER LEVEL CYCLONIC WIND FLOW SURROUNDS HISPANIOLA...THANKS TO THE CYCLONIC CIRCULATION CENTER OVER THE SW N ATLANTIC AND THE BAHAMAS. THE GFS MODEL FORECAST FOR 250 MB SHOWS THAT WESTERLY WIND FLOW WILL COVER HISPANIOLA WITH THE CURRENT CYCLONIC CIRCULATION CENTER...TO BE TO THE NORTH AND NORTHWEST OF HISPANIOLA. THE GFS MODEL FORECAST FOR 500 MB SHOWS THAT SOUTHERLY WIND FLOW WILL CROSS HISPANIOLA FOR THE NEXT 48 HOURS...WITH A NORTHEAST-TO- SOUTHWEST ORIENTED RIDGE. THE ATLANTIC OCEAN... A MIDDLE LEVEL TO UPPER LEVEL CYCLONIC CIRCULATION CENTER IS NEAR 24N75W...NEAR THE CENTRAL BAHAMAS. THE CYCLONIC CENTER IS COMPARATIVELY NOT AS WELL DEFINED AS IT HAS BEEN FOR THE LAST FEW DAYS. A SECOND CENTER WAS LOCATED NEAR 25N68W...WITH THE TWO CENTERS FORMING A BROAD CYCLONIC GYRE OVER THE SUBTROPICAL ATLC W OF 63W. THE ASSOCIATED CYCLONIC FLOW EXTENDS INTO THE CARIBBEAN SEA AND THE ATLANTIC OCEAN FROM 16N IN THE CARIBBEAN SEA...TO 30N IN THE ATLANTIC OCEAN...BETWEEN 60W AND 82W. PATCHES OF BROKEN TO OVERCAST MULTILAYERED CLOUDS COVER THE AREA FROM 22N TO 30N BETWEEN 72W AND THE COAST OF THE U.S. A MID-TO UPPER LEVEL TROUGH EXTENDS FROM A CYCLONIC CIRCULATION NEAR 30N37W THROUGH 24N47W TO 21N55W. THE TROUGH IS SURROUNDED BY COMPARATIVELY DRIER AIR IN SUBSIDENCE AS NOTED IN WATER VAPOR IMAGERY. THE EUMETSAT SEVERI SAL AND AIRMASS PRODUCTS INDICATED A VAST AREA OF DRY AIR AND SAHARAN DUST OVER A BROAD SECTION OF THE TROPICAL AND SUBTROPICAL ATLANTIC E OF 53W...ONE OF THE LARGEST AREAS OBSERVED THIS SEASON. A SURFACE RIDGE EXTENDS FROM THE MADEIRA ARCHIPELAGO...TO 26N25W...TO A 1028 MB HIGH PRESSURE CENTER THAT IS NEAR 27N41W...TO 27N66W...BEYOND CENTRAL FLORIDA...INTO THE GULF OF MEXICO. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ COBB