000 AXNT20 KNHC 221155 TWDAT TROPICAL WEATHER DISCUSSION... NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 AM EDT FRI AUG 22 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 INLAND OVER THE FLORIDA PENINSULA NEAR 29.6N 82.4W AT 22/1200 UTC OR JUST WEST OF GAINESVILLE FLORIDA. THIS POSITION IS ALSO ABOUT 43 NM NORTHEAST OF CEDAR KEY FLORIDA MOVING W AT 5 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 996 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. ON THE FORECAST TRACK...THE CENTER OF FAY IS EXPECTED TO CROSS THE NORTHERN FLORIDA PENINSULA TODAY...THEN MOVE NEAR OR OVER THE COAST OF THE FLORIDA PANHANDLE TONIGHT AND SATURDAY. HEAVY SHOWERS WITH EMBEDDED THUNDERSTORMS ARE WITHIN 120 NM OVER THE N SEMICIRCLE WITH SCATTERED/HEAVY SHOWERS WITH EMBEDDED THUNDERSTORMS WITHIN 90 NM OVER THE S SEMICIRCLE. OUTER RAIN BANDS OF SHOWERS WITH EMBEDDED ISOLATED THUNDERSTORMS ARE OVER A LARGER AREA FROM 24N-34N BETWEEN 76W-88W. ...TROPICAL WAVES... TROPICAL WAVE IS ALONG 38W/39W S OF 20N MOVING W NEAR 15 KT. CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE FROM 17N-20N BETWEEN 34W-40W. A SMALL 1008 MB LOW IS ANALYZED IN THE CENTRAL ATLC NEAR 12N52W MOVING W NEAR 15 KT. LOW IS EMBEDDED WITHIN THE ITCZ. ANY CONVECTION IS ASSOCIATED WITH THE ITCZ...SEE BELOW. TROPICAL WAVE IN THE W TROPICAL ATLC IS ALONG 59W S OF 16N MOVING W NEAR 10 KT. NO ASSOCIATED SHOWER ACTIVITY/CONVECTION. TROPICAL WAVE IN THE CENTRAL CARIBBEAN IS ALONG 81W/82W S OF 16N MOVING W NEAR 15 KT. NO ASSOCIATED SHOWERS/CONVECTION. ...THE ITCZ... THE ITCZ IS CENTERED ALONG 145N16W 13N292W 13N365W 1145NW 9N62W. SCATTERED STRONG CONVECTION IS WITHIN 60 NM OF THE ITCZ FROM 42W-45W. CLUSTERS OF SCATTERED MODERATE TO STRONG CONVECTION ARE FROM 3N-16N BETWEEN 40W-58W AND WITHIN 60 NM OF A LINE FROM 13N22W TO 10-23W. ...DISCUSSION... GULF OF MEXICO... T.S. FAY IS ONCE AGAIN A CONCERN FOR THE GULF AS IT CROSSES THE N FLORIDA PENINSULA TODAY INTO SAT...SEE SPECIAL FEATURES ABOVE. AN UPPER LEVEL RIDGE ANCHORED OVER SW MEXICO EXTENDS OVER THE W GULF FROM TEXAS TO THE W BAY OF CAMPECHE W OF 93W PRODUCING THIN HIGH CLOUDS OVER THE AREA WITH SCATTERED SHOWERS/ISOLATED THUNDERSTORMS FROM 22N-25N W OF 96W TO INLAND OVER MEXICO. AN UPPER HIGH ASSOCIATED WITH T.S. FAY COVERS THE NE GULF. A THIRD UPPER RIDGE COVERS THE REMAINDER OF THE S GULF ANCHORED ALONG THE N COAST OF W CUBA IN THE FLORIDA STRAITS. SCATTERED SHOWERS/ THUNDERSTORMS ARE IN THE BAY OF CAMPECHE S OF 20N TO INLAND OVER S MEXICO BETWEEN 92W-94W. THE CENTRAL GULF REMAINS CLEAR THIS MORNING WITH A WEAK 1015 MB HIGH OFF THE COAST OF LOUISIANA NEAR 28N91W. CARIBBEAN SEA... AN INDUCED INVERTED UPPER TROUGH EXTENDS FROM S NICARAGUA TO THE MONA PASSAGE SEPARATING AN UPPER RIDGE ANCHORED ALONG THE N COAST OF CUBA IN THE FLORIDA STRAITS AND A SECOND UPPER RIDGE ANCHORED JUST W OF THE WINDWARD ISLANDS NEAR 13N64W. THE ITCZ AXIS EXTENDS FROM COLOMBIA ACROSS PANAMA INTO THE E PACIFIC NEAR THE COSTA RICA BORDER AND COUPLED WITH THE UPPER INVERTED TROUGH IS GENERATING SCATTERED SHOWERS/THUNDERSTORMS W OF 72W AND SE OF A LINE FROM SW TIP OF HAITI TO THE NICARAGUA/COSTA RICA BORDER INCLUDING PORTIONS OF COLOMBIA...PANAMA...AND COSTA RICA. MODERATE EASTERLY TRADE WINDS WILL BEGIN TO DIMINISH TODAY BUT ARE CONTINUING TO USHER IN SOME ISOLATED SHOWERS/THUNDERSTORMS E OF 72W. THE NW CARIBBEAN IS DOMINATED BY MODERATE SUBSIDENCE AND DRY STABLE AIR...THUS CLEAR SKIES THERE AGAIN THIS MORNING. ATLANTIC OCEAN... THE MAIN CONCERN FOR THE FAR W ATLC AGAIN TODAY CONTINUES TO BE THE ACTIVITY ASSOCIATED WITH T.S. FAY...SEE SPECIAL FEATURES ABOVE. HOWEVER...THIS ACTIVITY WILL LESSEN AS FAY MOVES FURTHER W TODAY INTO SAT. THE UPPER HIGH ASSOCIATED WITH T.S. FAY COVERS THE W ATLC N OF 27N W OF 73W. A DEEP LAYERED TROUGH IS OVER THE NW ATLC TO 28N E OF T.S. FAY TO 62W WITH THE ASSOCIATED FRONTAL BOUNDARY N OF THE REGION. HOWEVER...IT IS INDUCING AN UPPER RIDGE TO THE E OF BERMUDA AND GENERATING SCATTERED SHOWERS/ THUNDERSTORMS N OF 24N FROM 61W-74W. AN UPPER LOW CENTERED NEAR 26N53W AND IS ENCROACHING ON THE UPPER RIDGE COVERING THE AREA FROM 17N-32N BETWEEN 50W-60W. A WEAK UPPER HIGH IS TO THE E NEAR 27N42W. AN E/W UPPER RIDGE COVERS THE E ATLC E OF 40W WITH AN UPPER TROUGH OVER THE NE ATLC TO 26N BETWEEN 33W AND THE CANARY ISLANDS. MODERATE SUBSIDENCE AND SOMEWHAT DRY STABLE AIR COVERS THE ATLC E OF 50W GIVING THAT AREA FAIR WEATHER CONDITIONS AGAIN THIS MORNING. A SURFACE RIDGE REMAINS OVER MOST OF THE ATLC N OF 23N E OF 60W ANCHORED BY A SERIES OF HIGHS N OF THE REGION. $$ WALLACE