000 AXNT20 KNHC 261801 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT FRI JUL 26 2013 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1715 UTC. ...SPECIAL FEATURE... THE CENTER OF TROPICAL STORM DORIAN AT 26/1500 UTC IS NEAR 17.7N 43.4W. DORIAN IS MOVING WEST-NORTHWESTWARD 18 KNOTS. THE ESTIMATED MINIMUM CENTRAL PRESSURE IS 1006 MB. THE MAXIMUM SUSTAINED WIND SPEEDS ARE 45 KNOTS WITH GUSTS TO 55 KNOTS. PLEASE READ THE FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT4/WTNT24 KNHC AND THE PUBLIC ADVISORY UNDER AWIPS/WMO HEADERS MIATCPAT4/WTNT34 KNHC FOR MORE DETAILS. CONVECTIVE PRECIPITATION...SCATTERED STRONG FROM 17N TO 19N BETWEEN 42W AND 44W. ...TROPICAL WAVES... A TROPICAL WAVE IS ALONG 91W FROM THE SOUTHWESTERN CORNER OF THE GULF OF MEXICO NEAR 21N SOUTHWARD. NO SIGNIFICANT DEEP CONVECTIVE PRECIPITATION IS APPARENT IN SATELLITE IMAGERY. ...THE ITCZ/THE MONSOON TROUGH... THE MONSOON TROUGH PASSES THROUGH THE SOUTHWESTERN COASTAL SENEGAL NEAR 13N17W...TO 10N21W AND 8N27W. THE ITCZ CONTINUES FROM 8N27W TO 7N34W AND 5N41W. CONVECTIVE PRECIPITATION... NUMEROUS STRONG FROM 7N TO 11N BETWEEN 14W AND 17W. SCATTERED MODERATE TO ISOLATED STRONG FROM 7N TO 10N BETWEEN 22W AND 27W...FROM 4N TO 7N BETWEEN 42W AND 51W...FROM 9N TO 10N BETWEEN 45W AND 47W...AND FROM 7N TO 9N BETWEEN 58W AND 60W IN GUYANA AND THE COASTAL WATERS OF VENEZUELA. ISOLATED MODERATE ELSEWHERE FROM 3N TO 10N TO THE EAST OF 40W. ...DISCUSSION... THE GULF OF MEXICO... MIDDLE LEVEL TO UPPER LEVEL NORTHEASTERLY WIND FLOW CROSSES INTO THE AREA FROM THE U.S.A. GULF COAST STATES...AND IT SPANS THE ENTIRE AREA. A WESTERN ATLANTIC OCEAN MIDDLE LEVEL TO UPPER LEVEL TROUGH PASSES THROUGH 32N75W TO 28N77W. THE TROUGH SUPPORTS A COLD FRONT THAT PASSES THROUGH 32N75W TO A 1015 MB LOW PRESSURE CENTER THAT IS NEAR 30N75W. A TROUGH EXTENDS FROM THE LOW CENTER TO 28N80W...ACROSS FLORIDA...TO 28N84W IN THE GULF OF MEXICO. A SECOND SURFACE TROUGH IS ABOUT 90 NM TO THE NORTH OF THE FIRST TROUGH... BETWEEN 79W AND 86W. COMPARATIVELY DRIER AIR IN SUBSIDENCE IN WATER VAPOR IMAGERY COVERS FLORIDA WITHIN 130 NM TO THE NORTHWEST OF LAKE OKEECHOBEE IN FLORIDA. A MIDDLE LEVEL TO UPPER LEVEL CYCLONIC CIRCULATION CENTER IS NEAR 17N92W BETWEEN THE ISTHMUS OF TEHUANTEPEC AND WESTERN GUATEMALA. COMPARATIVELY DRIER AIR IN SUBSIDENCE IN WATER VAPOR IMAGERY SURROUNDS THE CYCLONIC CENTER. A SURFACE RIDGE EXTENDS THE CENTRAL BAHAMAS...THROUGH THE FLORIDA STRAITS...TO A CENTRAL GULF OF MEXICO 1019 MB HIGH PRESSURE CENTER THAT IS NEAR 24N89W...TO THE MEXICO GULF COAST ALONG 24N. SURFACE ANTICYCLONIC WIND FLOW COVERS THE ENTIRE AREA. HIGH LEVEL CEILINGS ARE REPORTED IN TEXAS AT THE NAVAL AIR STATIONS IN KINGSVILLE AND IN CORPUS CHRISTI...AND IN THE HOUSTON METROPOLITAN AREA. LOW CLOUD CEILINGS ARE OBSERVED IN BAY CITY AND VICTORIA IN TEXAS. SCATTERED TO BROKEN HIGH CLOUDS ARE REPORTED IN THE NEW ORLEANS LOUISIANA METROPOLITAN AREA. MULTILAYERED CLOUD CEILINGS COVER THE AREA FROM SOUTHEASTERN MISSISSIPPI INTO ALABAMA NEAR MOBILE. HIGH CLOUD CEILINGS ARE OBSERVED IN THE FLORIDA PANHANDLE FROM DESTIN WESTWARD. LOW LEVEL CLOUD CEILINGS ARE REPORTED IN BROOKSVILLE AND AT THE TAMPA INTERNATIONAL AIRPORT. FAIR SKIES/CLEAR SKIES AT OR LOWER THAN 12000 FEET ARE BEING REPORTED ELSEWHERE. FOR THE OFFSHORE OIL PLATFORM SITES THAT ARE TO THE NORTH OF 27N TO THE WEST OF 88W... FAIR SKIES/CLEAR SKIES AT OR LOWER THAN 12000 FEET ARE BEING REPORTED ACROSS THE AREA. THE CARIBBEAN SEA... MIDDLE LEVEL TO UPPER LEVEL NORTHEASTERLY-TO-EASTERLY WIND FLOW COVERS THE AREA THAT IS TO THE NORTH OF 20N FROM SOUTHEASTERN CUBA WESTWARD. THIS WIND HAS MOVED FROM THE ATLANTIC OCEAN...BETWEEN THE 25N64W CYCLONIC CENTER AND FLORIDA...CROSSING CUBA...AND INTO THE NORTHWESTERN CORNER OF THE AREA. UPPER LEVEL SOUTHERLY TO SOUTHWESTERLY WIND FLOW COVERS THE AREA THAT IS TO THE SOUTH OF 16N82W 16N71W 18N64W. SOME OF THIS WIND FLOW MERGES WITH THE CYCLONIC WIND FLOW THAT IS MOVING AROUND THE 25N64W-TO-16N72W TROUGH. A MIDDLE LEVEL TO UPPER LEVEL CYCLONIC CIRCULATION CENTER IS NEAR 17N92W BETWEEN THE ISTHMUS OF TEHUANTEPEC AND WESTERN GUATEMALA. COMPARATIVELY DRIER AIR IN SUBSIDENCE IN WATER VAPOR IMAGERY SURROUNDS THE CYCLONIC CENTER. CYCLONIC WIND FLOW THAT IS MOVING AROUND THIS CENTER COVERS THE AREA TO THE WEST OF 84W. THE MONSOON TROUGH IS ALONG 8N/9N BETWEEN 73W IN COLOMBIA BEYOND 85W IN THE EASTERN PACIFIC OCEAN. CONVECTIVE PRECIPITATION...SCATTERED TO NUMEROUS STRONG TO THE SOUTH OF 12N83W 10N80W IN THE SOUTHWESTERN CORNER OF THE AREA. PLEASE READ THE HIGH SEAS FORECAST...MIAHSFAT2...AND THE OFFSHORE FORECAST...MIAOFFNT3...FOR MORE DETAILS ABOUT THE NORTHEAST TO EAST WINDS 25 TO 30 KNOTS AND SEA HEIGHTS TO 11 FEET FROM 11N TO 13N BETWEEN 72W AND 75W. EXPECT ALSO NORTHEAST TO EAST WINDS 20 TO 25 KNOTS AND SEA HEIGHTS TO 10 FEET ELSEWHERE FROM 11N TO 16N BETWEEN 71W AND 83W. HISPANIOLA... A MIDDLE LEVEL TO UPPER LEVEL CYCLONIC CIRCULATION CENTER IS NEAR 25N64W. A TROUGH CONTINUES SOUTHWARD FROM THE CYCLONIC CENTER TO THE MONA PASSAGE...AND TO 16N72W IN THE CARIBBEAN SEA. CONVECTIVE PRECIPITATION...RAINSHOWERS ARE POSSIBLE IN NORTHWESTERN PUERTO RICO...IN NORTHERN COASTAL AREAS OF THE DOMINICAN REPUBLIC NEAR 70W...AND IN THE NORTHWESTERN CORNER OF HAITI...AT THE MOMENT. THE 24-HOUR RAINFALL TOTAL IN INCHES...ACCORDING TO THE PAN AMERICAN TEMPERATURE AND PRECIPITATION TABLE...MIATPTPAN...FOR THE PERIOD ENDING AT 26/1200 UTC...WAS 0.29 IN ST. THOMAS. THE GFS FORECAST FOR 700 MB AND FOR 500 MB SHOWS THAT AN INVERTED TROUGH WILL COVER THE AREA FOR THE FIRST 24 HOURS OF THE FORECAST PERIOD. THE INVERTED TROUGH EVENTUALLY WILL SHIFT WESTWARD...PUTTING HISPANIOLA ON THE EASTERN SIDE OF THE TROUGH. THE GFS FORECAST FOR 250 MB SHOWS THAT A TROUGH WITH A NORTHEAST-TO-SOUTHWEST ORIENTATION WILL SPAN THE AREA FOR THE NEXT 48 HOURS. NO TROPICAL WAVE IS APPARENT FOR AT LEAST THE NEXT FEW DAYS. THE ATLANTIC OCEAN... A WESTERN ATLANTIC OCEAN MIDDLE LEVEL TO UPPER LEVEL TROUGH PASSES THROUGH 32N75W TO 28N77W. THE TROUGH SUPPORTS A COLD FRONT THAT PASSES THROUGH 32N75W TO A 1015 MB LOW PRESSURE CENTER THAT IS NEAR 30N75W. A TROUGH EXTENDS FROM THE LOW CENTER TO 28N80W...ACROSS FLORIDA...TO 28N84W IN THE GULF OF MEXICO. A SECOND SURFACE TROUGH IS ABOUT 90 NM TO THE NORTH OF THE FIRST TROUGH...BETWEEN 79W AND 86W. CONVECTIVE PRECIPITATION...WIDELY SCATTERED MODERATE TO ISOLATED STRONG IN THE ATLANTIC OCEAN TO THE NORTH OF 26N BETWEEN 70W AND 79W. COMPARATIVELY DRIER AIR IN SUBSIDENCE IN WATER VAPOR IMAGERY COVERS FLORIDA WITHIN 130 NM TO THE NORTHWEST OF LAKE OKEECHOBEE IN FLORIDA. A MIDDLE LEVEL TO UPPER LEVEL CYCLONIC CIRCULATION CENTER IS NEAR 25N64W. A TROUGH EXTENDS FROM THE CYCLONIC CENTER NORTHWARD TO 31N66W. THE TROUGH CONTINUES SOUTHWARD FROM THE CYCLONIC CENTER TO THE MONA PASSAGE...AND TO 16N72W IN THE CARIBBEAN SEA. CONVECTIVE PRECIPITATION...RAINSHOWERS ARE POSSIBLE IN NORTHWESTERN PUERTO RICO...IN NORTHERN COASTAL AREAS OF THE DOMINICAN REPUBLIC NEAR 70W...AND IN THE NORTHWESTERN CORNER OF HAITI. SCATTERED MODERATE TO STRONG WITHIN 200 NM ON EITHER SIDE OF 21N66W 27N64W 32N63W MIDDLE LEVEL TO UPPER LEVEL SOUTHWESTERLY WINDS...THAT ARE ON THE EASTERN SIDE OF THE 25N64W 16N72W TROUGH... MEET AN AREA OF MIDDLE LEVEL TO UPPER LEVEL SOUTHEASTERLY WIND FLOW...ROUGHLY IN THE AREA FROM 20N TO 30N ALONG 50W. CONVECTIVE PRECIPITATION...SCATTERED MODERATE TO ISOLATED STRONG FROM 25N TO 31N BETWEEN 49W AND 57W. A MIDDLE LEVEL TO UPPER LEVEL TROUGH PASSES THROUGH 32N18W TO 25N24W AND 20N28W. NO SIGNIFICANT DEEP CONVECTIVE PRECIPITATION IS APPARENT IN SATELLITE IMAGERY. BROAD SURFACE ANTICYCLONIC WIND FLOW COVERS THE ATLANTIC OCEAN TO THE NORTH OF 20N BETWEEN AFRICA AND 70W. ONE RIDGE PASSES THROUGH 32N45W TO 23N22W. A SECOND RIDGE PASSES THROUGH 32N52W TO 20N69W. PLEASE READ THE FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT4/WTNT24 KNHC...THE PUBLIC ADVISORY UNDER AWIPS/WMO HEADERS MIATCPAT4/WTNT34 KNHC...AND THE HIGH SEAS FORECAST... MIAHSFAT2...FOR MORE DETAILS ABOUT TROPICAL STORM DORIAN. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ MT