000 AXNT20 KNHC 100003 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT FRI SEP 09 2011 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... TROPICAL STORM NATE IS CENTERED NEAR 20.1N 92.9W AT 10/0000 UTC OR ABOUT 225 MI...3600 KM ENE OF VERACRUZ MEXICO... AND 300 MI...480 KM ESE OF TUXPAN MEXICO. NATE IS STATIONARY. ESTIMATED MINIMUM CENTRAL PRESSURE IS 998MB. THE MAXIMUM SUSTAINED WIND SPEED IS 45 KT WITH GUSTS TO 55 KT. PLEASE SEE THE LATEST INTERMEDIATE PUBLIC ADVISORY UNDER AWIPS/WMO HEADER MIATCPAT5/WTNT35 KNHC AND THE FULL FORECAST/ADVISORY UNDER AWIPS/WMO HEADER MIATCMAT5/ WTNT25 KNHC FOR MORE DETAILS. SCATTERED HEAVY SHOWERS/ISOLATED THUNDERSTORMS ARE S OF 23N TO INLAND OVER MEXICO AND THE YUCATAN PENINSULA BETWEEN 91W-97W. ADDITIONAL STRENGTHENING TO HURRICANE STATUS IS POSSIBLE BEFORE MAKING LANDFALL OVER MEXICO. TROPICAL STORM MARIA IS CENTERED NEAR 15.0N 59.1W AT 10/0000 UTC OR ABOUT 135 MI...215 KM N OF BARBADOS...OR ABOUT 185 MI...295 KM ESE OF GUADELOUPE MOVING NW AT 14 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 1004 MB. MAXIMUM SUSTAINED WIND SPEED IS 40 KT WITH GUSTS TO 50 KT. PLEASE SEE THE LATEST INTERMEDIATE PUBLIC ADVISORY UNDER AWIPS/WMO HEADER MIATCPAT4/ WTNT34 KNHC AND THE FULL FORECAST/ADVISORY UNDER AWIPS/WMO HEADER MIATCMAT4/WTNT24 KNHC FOR MORE DETAILS. SCATTERED MODERATE TO STRONG CONVECTION IS FROM 12N-17N BETWEEN 54W-58W. ISOLATED MODERATE CONVECTION IS ELSEWHERE FROM 10N-19N BETWEEN 50W-63W. TROPICAL STORM WARNINGS HAVE BEEN ISSUED FOR NUMEROUS ISLANDS IN THE LEEWARD ISLANDS. HURRICANE KATIA IS CENTERED NEAR 40.6N 62.7W AT 09/2100 UTC OR ABOUT 585 MI...940 KM N OF BERMUDA...OR ABOUT 280 MI...450 KM S OF HALIFAX NOVA SCOTIA MOVING ENE AT 33 KT. ESTIMATED MINIMUM CENTRAL PRESSURE WAS 970 MB...WITH MAXIMUM SUSTAINED WIND SPEED OF 70 KT WITH GUSTS TO 85 KT. PLEASE SEE THE LATEST INTERMEDIATE PUBLIC ADVISORY UNDER AWIPS/WMO HEADER MIATCPAT2/WTNT32 KNHC AND THE FULL FORECAST/ADVISORY UNDER AWIPS/WMO HEADER MIATCMAT2/ WTNT22 KNHC FOR MORE DETAILS. KATIA IS FORECAST TO BECOME POST-TROPICAL IN ABOUT 24 HOURS. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM 39N-46N BETWEEN 56W-64W. ...TROPICAL WAVES... TROPICAL WAVE IN THE CENTRAL TROPICAL ATLC IS ANALYZED FROM 18N35W TO 6N40W MOVING W NEAR 15 KT. WAVE IS EMBEDDED WITHIN AN AREA OF DEEP LAYER MOISTURE AS DEPICTED ON THE TOTAL PRECIPITABLE WATER IMAGERY AND IS WELL DEFINED IN THE LOW LEVEL CLOUD FIELD SATELLITE IMAGERY. SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS ARE WITHIN 180 NM ON EITHER SIDE OF THE WAVE AXIS. TROPICAL WAVE IN THE CENTRAL CARIBBEAN IS ANALYZED FROM 19N75W TO 11N77W MOVING W-NW NEAR 15 KT. WAVE IS EMBEDDED WITHIN AN AREA OF DEEP LAYER MOISTURE AS DEPICTED ON THE TOTAL PRECIPITABLE WATER IMAGERY. THE SOUTHERN EXTENSION OF THE WAVE AXIS IS INTERACTING WITH THE MONSOON TROUGH OVER THE SW CARIBBEAN. WIDELY SCATTERED CONVECTION IS E OF THE WAVE AXIS OVER HISPANIOLA AND THE CENTRAL CARIBBEAN FROM 13N-20N BETWEEN 68W-74W. ...THE ITCZ/THE MONSOON TROUGH... THE MONSOON TROUGH ENTERS THE TROPICAL E ATLANTIC AT THE SOUTHERN COAST OF GUINEA-BISSAU NEAR 11N15W AND EXTENDS W TO 9N17W 11N25W. FURTHER W...A PORTION OF THE ITCZ HAS REDEVELOPED FROM 9N43W TO 9N51W. ISOLATED MODERATE CONVECTION IS S OF THE MONSOON TROUGH FROM 6N-9N BETWEEN 20W-26W. SIMILAR CONVECTION IS ASSOCIATED WITH THE ITCZ FROM 3N-12N BETWEEN 43W-52W. ...DISCUSSION... GULF OF MEXICO... THE PRIMARY CONCERN TONIGHT IS TROPICAL STORM NATE...SEE SPECIAL FEATURES SECTION ABOVE. ELSEWHERE...AS OF 2100 UTC...A SURFACE TROUGH IS OVER CENTRAL FLORIDA AND THE NE GULF OF MEXICO ALONG 29N81W 26N87W. SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS ARE WITHIN 120 NM OF THE TROUGH. RADAR IMAGERY ALSO SHOWS SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS OVER FLORIDA S OF 29N. FAIR WEATHER IS NOTED OVER THE NW GULF AND TEXAS DUE TO UPPER LEVEL DRY AIR SUBSIDENCE. IN THE NEXT 24 HOURS EXPECT NATE TO REMAIN IN THE BAY OF CAMPECHE AND GRADUALLY INTENSIFY. ALSO EXPECT THE TROUGH TO DRIFT N WITH SHOWERS. CARIBBEAN SEA... THE OUTER WIND BANDS OF MARIA IS PRODUCING CONVECTION OVER THE EASTERN CARIBBEAN. SEE ABOVE. A TROPICAL WAVE IS ALSO OVER THE CENTRAL CARIBBEAN. SEE ABOVE. ELSEWHERE...WIDELY SCATTERED MODERATE CONVECTION IS NOTED INLAND OVER PORTIONS OF NW VENEZUELA...AND N COLOMBIA. SIMILAR CONVECTION IS OVER CENTRAL AMERICA FROM PANAMA TO S GUATEMALA. ISOLATED MODERATE CONVECTION IS OVER THE HIGHER ELEVATIONS OF JAMAICA...AND CUBA. THE NW CARIBBEAN IS UNDER UPPER LEVEL DRY AIR SUBSIDENCE BRINGING FAIR WEATHER CONDITIONS N OF HONDURAS. 10-20 KT TRADEWINDS DOMINATE THE CARIBBEAN WITH THE HIGHEST WINDS OVER THE E CARIBBEAN E OF 65W DUE TO THE APPROACH OF MARIA. EXPECT OVER THE NEXT 24 HOURS FOR MARIA TO HAMPER THE E CARIBBEAN...AND THE TROPICAL WAVE TO MOVE W TO THE W CARIBBEAN. ALSO EXPECT ADDITIONAL CONVECTION TO BE OVER THE SW CARIBBEAN DUE TO THE MONSOON TROUGH...AND OVER THE SW YUCATAN PENINSULA DUE TO NATE. ATLANTIC OCEAN... TROPICAL STORM MARIA...AND THE TROPICAL WAVE ARE THE DOMINANT WEATHER PRODUCERS IN THE TROPICAL ATLANTIC. A DISSIPATING STATIONARY FRONT IS OVER THE W ATLANTIC FROM 31N75W TO 28N80W. SCATTERED SHOWERS ARE WITHIN 90 NM OF THE FRONT. FURTHER E...A SURFACE TROUGH BROKE OFF FROM THE NORTHERN EXTENT OF THE TROPICAL WAVE THAT IS PRESENTLY OVER THE CENTRAL CARIBBEAN AND EXTENDS NEAR THE BAHAMAS FROM 27N72W TO 21N73W. SCATTERED SHOWERS ARE WITHIN 120 NM E OF THE TROUGH AXIS. THE TAIL END OF A COLD FRONT HAS ENTERED THE CENTRAL ATLANTIC NEAR 32N30W TO 30N49W. SCATTERED SHOWERS ARE WITHIN 60 NM OF THE FRONT. A 1020 MB HIGH IS CENTERED OVER THE CENTRAL ATLANTIC NEAR 33N52W. ANOTHER 1018 MB HIGH IS OVER THE E ATLANTIC NEAR 27N31W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ FORMOSA