000 AXNT20 KNHC 201155 TWDAT TROPICAL WEATHER DISCUSSION... NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT WED AUG 20 2008 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...METEOROLOGICAL ANALYSIS...WEATHER OBSERVATIONS...AND RADAR. BASED ON 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1015 UTC. ...SPECIAL FEATURES... TROPICAL STORM FAY IS CENTERED NEAR 28.5N 80.6W WHICH IS VERY NEAR CAPE CANAVERAL FLORIDA AT 20/1200 UTC MOVING NORTH AT 4 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 994 MB. MAXIMUM SUSTAINED WIND SPEED IS 40 KT WITH GUSTS TO 50 KT. PLEASE SEE THE LATEST NHC THE FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT1/WTNT21 KNHC AND PUBLIC ADVISORY UNDER AWIPS/WMO HEADERS MIATCPAT1/WTNT31 KNHC FOR MORE DETAILS. THE UPPER HIGH ASSOCIATED WITH FAY REMAINS ELONGATED E/W PROVIDING OUTFLOW OVER THE W ATLC TO 70W AND THE GULF OF MEXICO TO 86W. MOST OF THE HEAVY SHOWERS WITH EMBEDDED ISOLATED THUNDERSTORMS ARE NOW OFF THE E COAST OF FLORIDA FROM PALM BEACH COUNTY TO FLAGLER COUNTY. HEAVY SHOWERS WITH EMBEDDED THUNDERSTORMS ARE WITHIN 45 NM OF LINE FROM 22N77W OVER THE N BAHAMA ISLANDS TO 26N77W AND WITHIN 90/120 NM OF LINE FROM 27N76W ALONG 29N78W TO INLAND OVER NE FLORIDA NEAR 29N81W. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE FROM 26N TO THE STORM CENTER W OF 79W TO INLAND OVER CENTRAL FLORIDA. A 1010 MB LOW IS IN THE CENTRAL ATLC NEAR 13N38W DRIFTING W NEAR 5 KT. BROAD AREA OF DEEP LAYERED MOISTURE IS INDICATED BY MIMIC-TPW ANIMATION S OF 15N WITH A WELL DEFINED MID LEVEL LOW OBSERVED ON SATELLITE IMAGERY OVER THE LOW CENTER. CONVECTION HAS DECREASED OVER THE PAST 6 HOURS WITH CLUSTERS OF SCATTERED MODERATE CONVECTION FROM 10N-14N BETWEEN 39W-43W. ALTHOUGH ENVIRONMENTAL CONDITIONS ARE ONLY MARGINALLY FAVORABLE...SOME DEVELOPMENT OF THIS SYSTEM IS POSSIBLE OVER THE NEXT COUPLE OF DAYS AS IT MOVES SLOWLY WESTWARD. ...TROPICAL WAVES... TROPICAL WAVE IN THE CENTRAL ATLC WAS RELOCATED W OF THE PREVIOUS POSITION BASED ON SURFACE OBSERVATIONS AND SATELLITE IMAGERY ALONG 47W S OF 17N MOVING W 10-15 KT. NO ASSOCIATED CONVECTION. TROPICAL WAVE IN THE E CARIBBEAN REMAINS TILTED FROM 20N67W THOROUGH THE MONA PASSAGE TO THE COAST OF VENEZUELA NEAR 10N71W MOVING W NEAR 10 KT. NO ASSOCIATED SHOWERS/CONVECTION. ...THE ITCZ... THE ITCZ IS CENTERED ALONG 12N15W 9N25W 12N40W 11N51W 11N62W. SCATTERED/NUMEROUS STRONG CONVECTION IS FROM 8N-11N BETWEEN 31W-33W. CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE FROM 5N-10N BETWEEN 26W-44W AND AND WITHIN 60 NM OF LINE FROM 10N49W TO 13N57W. ...DISCUSSION... GULF OF MEXICO... ISOLATED SHOWERS ARE ALL THAT REMAIN OF T.S. FAY IN THE SE GULF OFF THE W COAST OF FLORIDA FROM THE FLORIDA KEYS TO 27N E OF 85W ACROSS THE FLORIDA PENINSULA. AN UPPER LOW REMAINS OVER NE TEXAS WITH THE UPPER LEVEL RIDGE ANCHORED OFF THE W COAST OF MEXICO EXTENDING INTO THE GULF ALONG 21N97W NE TO 25N90W GENERATING SOME SCATTERED SHOWERS/ISOLATED THUNDERSTORMS OVER THE W GULF W OF A LINE FROM FROM VERMILION BAY TO TUXPAN MEXICO. THE REMAINDER OF THE GULF REMAINS RATHER CLEAR THIS MORNING. CARIBBEAN SEA... AN UPPER RIDGE COVERS THE W CARIBBEAN W OF 71W WITH THE RIDGE AXIS EXTENDING FROM CENTRAL CUBA TO N BELIZE AND A SECOND UPPER RIDGE ANCHORED IN THE W TROPICAL ATLC COVERS THE E CARIBBEAN. THE ITCZ AXIS EXTENDS FROM COLOMBIA ALONG THE N COAST OF PANAMA ACROSS COSTA RICA INTO THE E PACIFIC GENERATING ISOLATED SHOWERS/ THUNDERSTORMS S OF 13N BETWEEN 74W-83W. SCATTERED SHOWERS/ ISOLATED THUNDERSTORMS ARE WITHIN 60 NM EITHER SIDE OF THE LESSER ANTILLES. THE REMAINDER OF THE CARIBBEAN IS DOMINATED BY MODERATE/STRONG SUBSIDENCE AND DRY STABLE AIR...THUS CLEAR SKIES ELSEWHERE THIS MORNING. ATLANTIC OCEAN... THE MAIN CONCERN FOR THE W ATLC AGAIN THIS MORNING IS THE ACTIVITY ASSOCIATED WITH T.S. FAY...SEE SPECIAL FEATURES ABOVE. THE ELONGATED UPPER LOW IN THE W/CENTRAL ATLC EXTENDS FROM NEAR BERMUDA SW TO 22N65W. A WEAK SURFACE TROUGH IS BENEATH THE UPPER LOW EXTENDING FROM 30N63W TO 26N67W. A LARGE UPPER LOW COVERS MOST OF THE CENTRAL ATLC CENTERED NEAR 23N49W WITH A WEAKER UPPER LOW NW OF THE CANARY ISLANDS NEAR 32N20W AND GENERATING ISOLATED SHOWERS AND POSSIBLE THUNDERSTORMS FROM 25N-29N BETWEEN 63W-67W. BOTH OF THESE LOWS ARE BENIGN FEATURES. MODERATE SUBSIDENCE AND SOMEWHAT DRY STABLE AIR COVERS THE ATLC E OF 70W GIVING THE REMAINDER OF THE AREA FAIR WEATHER CONDITIONS AGAIN THIS MORNING. A SURFACE RIDGE CONTINUES TO DOMINATE MOST OF THE ATLC N OF 20N E OF 70W WITH A WEAKNESS NEAR THE SURFACE TROUGH ANCHORED BY A SERIES OF HIGHS N OF THE REGION. $$ WALLACE