000 AXNT20 KNHC 102358 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT FRI OCT 10 2014 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2315 UTC. ...SPECIAL FEATURES... SUBTROPICAL DEPRESSION SEVEN WAS UPGRADED TO SUBTROPICAL STORM FAY AT 10/2100 UTC. SUBTROPICAL STORM FAY IS CENTERED NEAR 25.2N 64.2W AT 10/2330 UTC OR ABOUT 42 NM S OF BERMUDA MOVING N-NW AT 10 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 1000 MB. MAXIMUM SUSTAINED WINDS SPEED IS 50 KT WITH GUSTS TO 60 KT. DATA FROM AN AIR FORCE RESERVE HURRICANE HUNTER AIRCRAFT INDICATE THAT MAXIMUM SUSTAINED WINDS HAVE INCREASED AND SOME ADDITIONAL STRENGTHENING IS FORECAST TONIGHT. SCATTERED MODERATE TO SCATTERED STRONG CONVECTION IS FROM 25N-27N BETWEEN 64W-67W. CONVECTION FURTHER N AND E IS ASSOCIATED WITH AN UPPER RIDGE. SEE ATLANTIC SECTION BELOW. SEE THE LATEST FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT2/WTNT22 KNHC AND THE INTERMEDIATE PUBLIC ADVISORY UNDER AWIPS/WMO HEADERS MIATCPAT2/ WTNT32 FOR MORE DETAILS. ...TROPICAL WAVES... TROPICAL WAVE W OF THE CAPE VERDE ISLANDS EXTENDS FROM 17N29W TO NEAR 9N33W MOVING W NEAR 10 KT OVER THE PAST 24 HOURS. WAVE REMAINS EMBEDDED WITHIN A SURGE OF DEEP MOISTURE AS DEPICTED ON TOTAL PRECIPITABLE WATER IMAGERY. A MID LEVEL LOW IS ALONG THE WAVE NEAR 15N30W. SCATTERED MODERATE CONVECTION IS FROM 12N-17N BETWEEN 28W-33W. TROPICAL WAVE APPROACHING THE LESSER ANTILLES WAS REESTABLISHED ALONG 59W/60W FROM 9N-15N MOVING W 10-15 KT OVER THE PAST 24 HOURS. THE SURFACE 1011 MB LOW REMAINS NEAR 15N52W AND IS CONSIDERED A SEPARATE FEATURE. WAVE IS EMBEDDED WITHIN A BROAD AREA OF MOISTURE AS DEPICTED ON TOTAL PRECIPITABLE WATER IMAGERY WITH NO ASSOCIATED DEEP CONVECTION SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS ARE FROM 11N-14N BETWEEN 56W- 60W. TROPICAL WAVE OVER THE W CARIBBEAN IS ALONG 84W FROM 19N TO INLAND OVER HONDURAS TO COSTA RICA NEAR 16N MOVING W 20-25 KT OVER THE PAST 24 HOURS. WAVE REMAINS EMBEDDED WITHIN AN AREA OF MOISTURE AS DEPICTED ON TOTAL PRECIPITABLE WATER IMAGERY. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM 10N-17N BETWEEN 80W-85W. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS ACROSS AFRICA INTO THE TROPICAL ATLC NEAR 12N16W AND CONTINUES TO 10N20W WHERE THE ITCZ BEGINS AND CONTINUES TO 12N30W THEN RESUMES W OF THE TROPICAL WAVE NEAR 11N35W AND CONTINUES ALONG 7N44W TO SOUTH AMERICA NEAR 5N53W. SCATTERED MODERATE/STRONG CONVECTION IS FROM 4N-12N BETWEEN 23W- 30W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM 5N- 12N BETWEEN 33W-44W. ...DISCUSSION... GULF OF MEXICO... AN UPPER RIDGE ANCHORED OVER THE W GULF OF MEXICO NEAR 27N93W DOMINATES THE GULF N OF 23N WITH STRONG SUBSIDENCE AND DRY/STABLE AIR OVER THE SAME AREA. AN UPPER RIDGE ANCHORED OVER THE W CARIBBEAN COVERS THE E BAY OF CAMPECHE E OF 94W WHILE A WEAK UPPER LOW THAT IS INLAND OVER MEXICO NEAR MEXICO CITY COVERS THE REMAINDER OF THE BAY OF CAMPECHE. DIFFLUNCE BETWEEN THESE UPPER LEVEL FEATURES IS GENERATING SCATTERED SHOWERS/ ISOLATED THUNDERSTORMS INLAND AND ALONG THE IMMEDIATE COAST OF THE YUCATAN S OF 21N E OF 93W. A WEAK SURFACE RIDGE COVERS THE GULF ANCHORED BY A 1018 MB HIGH NEAR APALACHEE BAY FLORIDA AND EXTENDS AN AXIS SW TO TAMPICO MEXICO. THE REMAINDER OF THE GULF IS UNDER CLEAR SKIES THIS EVENING. SURFACE RIDGE WILL PERSIST THROUGH THE WEEKEND BUT WILL BEGIN TO RETREAT E SUN NIGHT THROUGH MON NIGHT IN RESPONSE TO A STRONG COLD FRONT THAT MOVES OFF THE TEXAS COAST MON NIGHT. CARIBBEAN SEA... AN UPPER RIDGE DOMINATES THE CARIBBEAN W OF 67W AND IS ANCHORED OVER THE W CARIBBEAN NEAR 12N80W. THIS IS DRAWING TROPICAL MOISTURE ACROSS CENTRAL AMERICA AND THE N CARIBBEAN GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS N OF 18N E OF 64W INCLUDING THE GREATER ANTILLES...JAMAICA...AND THE YUCATAN PENINSULA. THE REMAINDER OF THE CARIBBEAN IS UNDER CLEAR SKIES THIS EVENING. TROPICAL WAVE IN THE W CARIBBEAN WILL MOVE INLAND OVER THE YUCATAN PENINSULA SAT NIGHT AND DISSIPATE. A SECOND TROPICAL WAVE WILL MOVE INTO THE CARIBBEAN EARLY SAT REACHING THE W CARIBBEAN BY MON. ...HISPANIOLA... SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE OBSERVED ACROSS THE ISLAND THIS EVENING DUE TO THE UPPER RIDGE OVER THE W CARIBBEAN DRAWING TROPICAL MOISTURE ACROSS THE N CARIBBEAN. THIS UPPER RIDGE WILL SHIFT W AS AN UPPER TROUGH DROPS S FROM THE W ATLC BY LATE SAT GIVING THE ISLAND EASTERLY FLOW ALOFT. THIS WILL CONTINUE TO GIVE HISPANIOLA SHOWERS/THUNDERSTORMS THROUGH MOST OF THE WEEKEND ESPECIALLY COUPLED WITH DAYTIME HEATING IN THE AFTERNOON/EVENING INCREASING INSTABILITY. ATLANTIC OCEAN... PRIMARY CONCERN THIS EVENING IS SUBTROPICAL STORM FAY IN THE SPECIAL FEATURES ABOVE. WEAK SURFACE RIDGE COVERS THE W ATLC W OF 70W ANCHORED IN THE GULF OF MEXICO. AN UPPER TROUGH EXTENDS OVER THE W ATLC THROUGH 32N73W TO 24N74W. THE UPPER RIDGE OVER THE W CARIBBEAN COVERS THE GREATER ANTILLES PROVIDING DIFFLUNCE ALOFT TO GENERATE SCATTERED SHOWERS/ISOLATED THUNDERSTORMS S OF 25N TO OVER THE GREATER ANTILLES BETWEEN 72W-80W. AN UPPER RIDGE IS E OF FAY AND IS ANCHORED NEAR 25N56W COVERING THE CENTRAL ATLC. THIS UPPER RIDGE IS PROVIDING DIFFLUNCE ALOFT THE GENERATE CLUSTERS OF SCATTERED MODERATE WITH EMBEDDED CLUSTERS OF SCATTERED STRONG CONVECTION WITHIN 150 NM OF LINE FROM 20N55W TO 25N57W AND WITHIN 175/200 NM OF LINE FROM 25N57W TO 30N61W. AN UPPER TROUGH EXTENDS INTO THE E ATLC THROUGH 32N22W TO 24N31W THEN NARROWING TO 20N48W AND IS SUPPORTING A SURFACE TROUGH THAT EXTENDS INTO THE REGION NEAR 32N18W TO 26N27W. A SURFACE RIDGE COVERS THE CENTRAL AND E ATLC N OF 20N BETWEEN 20W-55W WITH A WEAKNESS IN THE IMMEDIATE VICINITY OF THE ABOVE SURFACE TROUGH AND IS ANCHORED BY A 1027 MB HIGH NEAR 35N42W. A 1011 MB LOW IS IN THE W TROPICAL ATLC NEAR 15N52W GENERATING SCATTERED MODERATE/STRONG CONVECTION FROM 13N-15N BETWEEN 50W-53W. W ATLC SURFACE RIDGE WILL PERSIST THROUGH MON AS FAY MOVES NORTHERLY THROUGH SAT NIGHT WHEN IT IS EXPECTED TO TURN TO THE NE OUT OF THE DISCUSSION AREA. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ PAW