000 AXNT20 KNHC 191759 TWDAT TROPICAL WEATHER DISCUSSION... NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT TUE AUG 19 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1715 UTC. ...SPECIAL FEATURES... TROPICAL STORM FAY IS CENTERED NEAR 27.0N 81.1W WHICH IS INLAND OVER SOUTH FLORIDA NEAR LAKEPORT FLORIDA AND ALSO ABOUT 22 NM SOUTHWEST OF LAKE OKEECHOBEE AT 19/1800 UTC MOVING NORTH-NORTHEAST AT 7 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 986 MB. MAXIMUM SUSTAINED WIND SPEED IS 55 KT WITH GUSTS TO 65 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. DOPPLER RADAR AND SATELLITE PRESENTATIONS REMAIN IMPRESSIVE OVER SOUTH FLORIDA THIS AFTERNOON WITH FAY REMAINING EMBEDDED IN A VERY WEAK AND NARROW UPPER TROUGH WHICH EXTENDS FROM THE ERN U.S. SEABOARD THROUGH CENTRAL FLORIDA TO THE YUCATAN CHANNEL. THIS UPPER TROUGH IS STEERING THE STORM N-NE WITH FLUCTUATIONS IN INTENSITY EXPECTED THROUGH WEDNESDAY MORNING AS FAY TRAVELS ACROSS THE PENINSULA. SOME RESTRENGTHENING IS THEN FORECAST ONCE FAY MOVES BACK OVER THE W ATLC WATERS BY WEDNESDAY. THE MAIN CORE OF SCATTERED MODERATE/STRONG CONVECTION IS FROM 25N-30N BETWEEN 79W-83W. SIMILAR CONVECTION IS LOCATED OVER THE W ATLC WATERS FROM 24N-31N BETWEEN 75W-79W. SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS ARE OVER THE REMAINDER OF THE AREA FROM 21N-32N BETWEEN 74W-84W. FAY IS EXPECTED TO PRODUCE RAINFALL ACCUMULATIONS OF 5 TO 10 INCHES OVER THE SOUTHERN AND EAST-CENTRAL FLORIDA PENINSULA...WITH MAXIMUM TOTAL AMOUNTS OF 15 INCHES. ACCUMULATIONS OF 3 TO 5 INCHES ARE POSSIBLE IN THE NORTHWESTERN BAHAMAS. ISOLATED TORNADOES ARE ALSO POSSIBLE TODAY OVER THE EASTERN HALF OF THE FLORIDA PENINSULA. ...TROPICAL WAVES... TROPICAL WAVE IN THE E TROPICAL ATLC IS ALONG 37W S OF 17N WITH A 1009 MB LOW ALONG THE WAVE NEAR 13N MOVING W NEAR 10 KT. BROAD AREA OF DEEP LAYERED MOISTURE IS INDICATED BY MIMIC-TPW ANIMATION WITH A WELL DEFINED MID-LEVEL LOW OBSERVED ON SATELLITE IMAGERY. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM 11N-14N BETWEEN 36W-39W. TROPICAL WAVE IN THE E CARIBBEAN/W TROPICAL ATLC REMAINS TILTED FROM 20N63W ACROSS THE VIRGIN ISLANDS TO THE COAST OF VENEZUELA NEAR 11N68W MOVING W 10-15 KT. NO ASSOCIATED SHOWERS/CONVECTION. ...THE ITCZ... THE ITCZ IS CENTERED ALONG 13N16W 11N25W 12N35W 12N40W 10N50W 7N60W. CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE FROM 6N-12N BETWEEN 15W-28W...FROM 8N-12N BETWEEN 27W-32W... AND FROM 5N-8N BETWEEN 33W-41W. ...DISCUSSION... GULF OF MEXICO... THE PRIMARY CONCERN FOR THE ERN GULF IS T.S. FAY AS IT MOVES ACROSS THE FLORIDA PENINSULA THIS AFTERNOON...SEE SPECIAL FEATURES ABOVE. NARROW UPPER TROUGH IS OVER THE FAR ERN U.S. TO ACROSS THE FLORIDA PENINSULA. AN UPPER LOW IS MOVING SE OVER N TEXAS AND OKLAHOMA WITH AN UPPER LEVEL RIDGE ANCHORED OVER THE CENTRAL GULF NEAR 26N91W EXTENDING WEAK RIDGE AXIS ACROSS THE FLORIDA PANHANDLE. AT THE SURFACE...A STATIONARY FRONTAL BOUNDARY IS INLAND ALONG THE GULF COAST FROM MOBILE ALABAMA TO AUSTIN TEXAS. THIS SCENARIO IS GENERATING SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS OVER THE NW GULF W OF A LINE FROM NEW ORLEANS LOUISIANA TO BROWNSVILLE TEXAS. THE CENTRAL AND S GULF REMAIN RATHER CLEAR WITH A NARROW CORRIDOR OF HIGHER PRESSURE AND LIGHTER WIND VALUES ALONG 90W. THE FLORIDA PENINSULA AND THE FAR E GULF WILL CONTINUE TO FEEL THE EFFECTS OF T.S. FAY AS IT MOVES IN A NORTHERLY DIRECTION. CARIBBEAN SEA... AN UPPER RIDGE AXIS EXTENDS FROM THE CENTRAL BAHAMAS ACROSS CUBA TO THE GULF OF HONDURAS GIVING MOST OF THE CARIBBEAN EASTERLY UPPER FLOW WITH STRONGER NE UPPER FLOW BETWEEN 70W-80W. THIS IS PROVIDING UPPER LEVEL DIFFLUENCE TO GENERATE SCATTERED SHOWERS/THUNDERSTORMS ACROSS CENTRAL CUBA AND ADJACENT COASTAL WATERS FROM 21N-23N BETWEEN 78W-83W. THE ITCZ AXIS EXTENDS FROM COLOMBIA INTO THE E PACIFIC JUST N OF PANAMA GENERATING SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS OVER THE FAR SW CARIBBEAN S OF 11N BETWEEN COLOMBIA AND COSTA RICA. AN AREA OF SCATTERED SHOWERS AND THUNDERSTORMS IS ACROSS THE WINDWARD ISLANDS SOUTH OF DOMINICA IN THE SE CARIBBEAN FROM 8N-15N BETWEEN 59W-63W DUE TO UPPER LEVEL DIFFLUENCE FROM A CENTRAL ATLC RIDGE AXIS ALONG 55W. THE REMAINDER OF THE CARIBBEAN IS DOMINATED BY MODERATE/STRONG SUBSIDENCE AND DRY STABLE AIR... THUS CLEAR SKIES PREVAIL THIS AFTERNOON. ATLANTIC OCEAN... THE MAIN CONCERN FOR THE SW ATLC WATERS IS T.S. FAY...SEE SPECIAL FEATURES ABOVE. SCATTERED MODERATE TO STRONG CONVECTION IS W OF 74W AND N OF 24N. AN UPPER LOW IS IN THE W/CENTRAL ATLC NEAR 25N63W EXTENDING A NARROW UPPER TROUGH TO N OF THE VIRGIN ISLANDS AND PUERTO RICO. A WEAK SURFACE TROUGH IS N OF THE UPPER LOW EXTENDING FROM 32N60W TO 26N66W. AN AREA OF SCATTERED SHOWERS IS SE OF THE SURFACE TROUGH FROM 22N-27N BETWEEN 59W-62W. AN UPPER RIDGE IS TO THE E EXTENDING FROM 15N55W TO BEYOND 32N55W. A LARGE UPPER LOW COVERS MOST OF THE E/CENTRAL ATLC NEAR 22N43W WITH A WEAKER UPPER LOW NW OF THE CANARY ISLANDS NEAR 31N21W. MODERATE SUBSIDENCE AND SOMEWHAT DRY STABLE AIR COVERS THE ATLC E OF 55W GIVING THE REMAINDER OF THE AREA FAIR WEATHER CONDITIONS. A SURFACE RIDGE CONTINUES TO DOMINATE MOST OF THE ATLC N OF 20N E OF 55W WITH A WEAKNESS NEAR THE SURFACE TROUGH ANCHORED BY A SERIES OF HIGHS N OF THE REGION. $$ HUFFMAN