000 AXNT20 KNHC 220552 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0415 UTC. ...SPECIAL FEATURES... TROPICAL STORM FAY IS CENTERED NEAR 29.4N 81.4W AT 22/0600 UTC OR ABOUT 44 NM WEST-NORTHWEST OF DAYTONA BEACH FLORIDA MOVING W AT 4 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 995 MB. MAXIMUM SUSTAINED WIND SPEED IS 45 KT WITH GUSTS TO 55 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. FAY IS DRIFTING TOWARD THE WEST NEAR 2 MPH...4 KM/HR. FAY IS FORECAST TO CONTINUE TO MOVE WESTWARD OR WEST-NORTHWESTWARD WITH SOME INCREASE IN FORWARD SPEED DURING THE NEXT COUPLE OF DAYS. ON THIS TRACK...THE CENTER OF FAY IS EXPECTED TO MOVE SLOWLY ACROSS THE NORTHERN FLORIDA PENINSULA TODAY...AND MOVE NEAR OR OVER THE FLORIDA PANHANDLE COAST ON LATE TONIGHT AND SATURDAY. HEAVY SHOWERS WITH EMBEDDED THUNDERSTORMS ARE WITHIN 120 NM OVER THE N SEMICIRCLE WITH SCATTERED/HEAVY SHOWERS WITH EMBEDDED THUNDERSTORMS OVER THE S SEMICIRCLE. OUTER RAIN BANDS OF SHOWERS WITH EMBEDDED ISOLATED THUNDERSTORMS ARE OVER A LARGE AREA FROM 25N-33N BETWEEN 76W 85W. FAY IS EXPECTED TO PRODUCE RAINFALL ACCUMULATIONS OF 5 TO 10 INCHES OVER CENTRAL AND NORTHERN PORTIONS OF THE FLORIDA PENINSULA...THE FLORIDA PANHANDLE...SOUTHERN GEORGIA...AND SOUTHEASTERN ALABAMA...WITH ISOLATED MAXIMUM AMOUNTS OF 15 INCHES POSSIBLE. RAINFALL TOTALS OF 2 TO 4 INCHES ARE POSSIBLE ACROSS THE COASTAL AREAS OF SOUTHERN SOUTH CAROLINA. ADDITIONAL RAINFALL AMOUNTS OF 1 TO 2 INCHES ARE POSSIBLE IN OUTER RAIN BANDS OVER SOUTHERN FLORIDA. ISOLATED STORM TOTAL ACCUMULATIONS OF 20 TO 30 INCHES HAVE BEEN OBSERVED WITH THIS SYSTEM OVER THE EAST CENTRAL COASTAL AREAS OF FLORIDA. ...TROPICAL WAVES... TROPICAL WAVE IS ALONG 37W S OF 19N MOVING W NEAR 15 KT. SCATTERED MODERATE/STRONG CONVECTION IS FROM 17N-19N BETWEEN 35W-37W WITH CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION FROM 15N-19N BETWEEN 31W-35W. A SMALL 1008 MB LOW IS ANALYZED IN THE CENTRAL ATLC NEAR 12N50W 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 57W/58W S OF 16N MOVING W NEAR 10 KT. NO ASSOCIATED SHOWER ACTIVITY/CONVECTION. TROPICAL WAVE IN THE CENTRAL CARIBBEAN IS ALONG 79W/80W S OF 16N MOVING W NEAR 15 KT. NO ASSOCIATED SHOWERS/CONVECTION. ...THE ITCZ... THE ITCZ IS CENTERED ALONG 15N16W 13N22W 13N35W 12N52W 9N62W. SCATTERED STRONG CONVECTION IS WITHIN 90 NM S OF THE ITCZ FROM 41W-43W. CLUSTERS OF SCATTERED MODERATE TO STRONG CONVECTION ARE FROM 3N-16N BETWEEN 37W-55W AND WITHIN 120 NM OF THE ITCZ BETWEEN 17W-23W. ...DISCUSSION... GULF OF MEXICO... T.S. FAY IS BECOMING A CONCERN FOR THE GULF AGAIN AS IT IS EXPECTED TO CROSS THE N FLORIDA PENINSULA TONIGHT INTO FRI... SEE SPECIAL FEATURES ABOVE. AN UPPER LEVEL RIDGE ANCHORED OVER SW MEXICO EXTENDS ACROSS S TEXAS TO SE LOUISIANA COVERING THE W GULF W OF 93W. AN UPPER HIGH ASSOCIATED WITH T.S. FAY COVERS THE NE GULF. THESE UPPER FEATURES ARE BRINGING THIN HIGH CLOUDS TO THE W GULF AND THE NE GULF LEAVING THE REMAINDER OF THE GULF CLEAR TONIGHT. A THIRD UPPER RIDGE COVERS THE SE GULF ANCHORED OVER W CUBA. A WEAK 1015 MB HIGH IS OFF THE SE COAST OF LOUISIANA NEAR 28N90W. CARIBBEAN SEA... A WEAK UPPER LOW IS JUST S OF THE DOMINICAN REPUBLIC NEAR 18N69W EXTENDING A SHEAR AXIS SW TO 12N79W. THIS SHEAR AXIS IS SEPARATING AN UPPER RIDGE ANCHORED OVER W CUBA AND A SECOND UPPER RIDGE ANCHORED JUST E OF THE ABC ISLANDS. THE ITCZ AXIS EXTENDS FROM COLOMBIA ACROSS PANAMA INTO THE E PACIFIC NEAR THE COSTA RICA BORDER AND COUPLED WITH THE SHEAR AXIS ARE GENERATING SCATTERED SHOWERS/THUNDERSTORMS S OF 16N BETWEEN 74W-83W. SIMILAR ACTIVITY IS WITHIN 60 NM ALONG THE SE COAST OF CUBA. MODERATE EASTERLY TRADE WINDS CONTINUE OVER THE AREA AND COUPLED WITH ADVECTED TROPICAL MOISTURE FROM THE UPPER RIDGE OVER THE E CARIBBEAN ARE USHERING IN ISOLATED SHOWERS/THUNDERSTORMS E OF 72W. THE NW CARIBBEAN IS DOMINATED BY MODERATE SUBSIDENCE AND DRY STABLE AIR...THUS CLEAR SKIES THERE TONIGHT. ATLANTIC OCEAN... THE MAIN CONCERN FOR THE FAR W ATLC AGAIN TONIGHT CONTINUES TO BE THE ACTIVITY ASSOCIATED WITH T.S. FAY...SEE SPECIAL FEATURES ABOVE. THE UPPER HIGH ASSOCIATED WITH T.S. FAY COVERS THE W ATLC N OF 27N W OF 71W. 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 56W-67W. A SECOND UPPER LOW IS ENCROACHING ON THE UPPER RIDGE COVERING THE AREA FROM 18N-32N BETWEEN 53W-59W AND CENTERED NEAR 27N56W. A WEAK UPPER HIGH IS TO THE E NEAR 26N40W. AN E/W UPPER RIDGE COVERS THE E ATLC WITH AN UPPER TROUGH OVER THE NE ATLC TO 28N BETWEEN 31W AND THE CANARY ISLANDS. MODERATE SUBSIDENCE AND SOMEWHAT DRY STABLE AIR COVERS THE ATLC E OF 50W GIVING THAT AREA FAIR WEATHER CONDITIONS TONIGHT. A SURFACE RIDGE REMAINS OVER MOST OF THE ATLC N OF 20N E OF 70W ANCHORED BY A SERIES OF HIGHS N OF THE REGION. $$ WALLACE