000 AXNT20 KNHC 241206 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT WED AUG 24 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1115 UTC. ...SPECIAL FEATURE... HURRICANE IRENE IS CENTERED NEAR 21.9N 73.3W AT 24/1200 UTC OR ABOUT 55 MI...85 KM SE OF ACKLINS ISLAND BAHAMAS...OR ABOUT 335 MI...540 KM SE OF NASSAU MOVING W-NW AT 8 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 957 MB. MAXIMUM SUSTAINED WIND SPEED IS 95 KT WITH GUSTS TO 115 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/NUMEROUS STRONG CONVECTION IS WITHIN 75 NM IN ALL QUADRANTS. SCATTERED/HEAVY SHOWERS WITH EMBEDDED ISOLATED THUNDERSTORMS COVER THE REMAINDER OF THE AREA FROM 20N-24N BETWEEN 70W-75W INCLUDING HISPANIOLA...TURKS AND CAICOS...TO OVER THE S BAHAMA ISLANDS. HURRICANE FORCE WINDS EXTEND OUTWARD UP TO 40 NM FROM THE CENTER AND TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 200 NM FROM THE CENTER. IRENE IS A NOW A MAJOR HURRICANE. SOME ADDITIONAL STRENGTHENING IS FORECAST FOR TODAY. IRENE IS EXPECTED TO PRODUCE ADDITIONAL RAINFALL ACCUMULATIONS OF 1-3 INCHES ACROSS PUERTO RICO AND HISPANIOLA. ISOLATED MAXIMUM STORM TOTAL AMOUNTS OF 15 INCHES ARE POSSIBLE IN ASSOCIATION WITH IRENE. THESE RAINS COULD CAUSE LIFE THREATENING FLASH FLOODS AND MUD SLIDES IN AREAS OF STEEP TERRAIN. RAINFALL ACCUMULATIONS OF 6 TO 12 INCHES ARE EXPECTED IN THE BAHAMAS...AND THE TURKS AND CAICOS ISLANDS. A 1007 MB LOW IS CENTERED S OF THE CAPE VERDE ISLANDS NEAR 13N23W WITH SCATTERED/NUMEROUS STRONG CONVECTION FROM 11N-14N BETWEEN 23W-28W. SHOWER/THUNDERSTORM ACTIVITY HAS INCREASED AND BECOME A LITTLE BETTER ORGANIZED TONIGHT AND ENVIRONMENTAL CONDITIONS APPEAR GENERALLY FAVORABLE FOR SLOW DEVELOPMENT OF THIS LOW DURING THE NEXT SEVERAL DAYS. THIS SYSTEM HAS A MEDIUM CHANCE OF BECOMING A TROPICAL CYCLONE DURING THE NEXT 48 HOURS AS IT MOVES WESTWARD AT 9-13 KT. ...THE ITCZ/THE MONSOON TROUGH... THE MONSOON TROUGH IS ANALYZED ACROSS AFRICA ENTERING THE E TROPICAL ATLC NEAR 19N16W THROUGH THE 1007 MB LOW IN THE SPECIAL FEATURES TO NEAR 10N31W THE ITCZ AXIS EXTENDS FROM 8N37W ALONG 7N46W TO 11N58W. SCATTERED MODERATE/STRONG CONVECTION IS FROM 8N-12N BETWEEN 26W-31W. CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE FROM 7N-14N BETWEEN 50W-59W. ...DISCUSSION... GULF OF MEXICO... BROAD UPPER RIDGE CONTINUES TO DOMINATE MOST OF THE GULF ANCHORED OVER CENTRAL TEXAS. A SHORTWAVE UPPER TROUGH IS OVER THE NE GULF EXTENDING FROM AN UPPER LOW OFF THE SOUTH CAROLINA COAST ACROSS NE FLORIDA BETWEEN JACKSONVILLE AND TALLAHASSEE INTO THE GULF TO NEAR 27N85W SUPPORTING A SURFACE TROUGH THAT AT 24/0900 UTC EXTENDS FROM THE COAST OF FLORIDA NEAR PENSACOLA TO 27N85W GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS FROM 27N-30N BETWEEN 86W-88W. A WEAK SURFACE RIDGE EXTENDS FROM THE W ATLC ACROSS FLORIDA WITH A 1013 MB HIGH NEAR 28N89W. UPPER LEVEL CONVERGENCE OVER THE SE GULF BETWEEN THE UPPER SHORTWAVE TROUGH OVER THE NE GULF AND AN INVERTED UPPER TROUGH OVER THE YUCATAN PENINSULA ARE GENERATING ISOLATED SHOWERS/THUNDERSTORMS S OF 26N BETWEEN 81W-87W INCLUDING THE LOWER FLORIDA KEYS. THE WEAK SURFACE RIDGE WILL LINGER OVER THE N GULF THROUGH SUN. HURRICANE IRENE IS EXPECTED MOVE OVER THE BAHAMAS TODAY WITH TROPICAL STORM CONDITIONS EXPECTED TO REMAIN WELL E OF THE GULF WATERS. CARIBBEAN SEA... PRIMARY CONCERN THIS MORNING CONTINUES TO BE THE RAINS ACROSS THE NE CARIBBEAN ASSOCIATED WITH HURRICANE IRENE. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE N OF 17N BETWEEN 62W-73W INCLUDING THE VIRGIN ISLANDS...PUERTO RICO...AND HISPANIOLA. AN INVERTED UPPER TROUGH COVERS THE FAR NW CARIBBEAN EXTENDING INLAND OVER THE YUCATAN PENINSULA GENERATING ISOLATED SHOWERS/ THUNDERSTORMS W OF 83W THROUGH THE YUCATAN CHANNEL. THE MONSOON TROUGH EXTENDS FROM COLOMBIA ACROSS E PANAMA ALONG 9N80W THEN NW ACROSS NICARAGUA NEAR 11N84W INTO THE E PACIFIC REGION GENERATING SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS S OF 10N BETWEEN COLOMBIA AND COSTA RICA. HURRICANE IRENE IS EXPECTED TO MOVE NW ACROSS BAHAMAS TODAY THROUGH THU. WINDS OVER THE NE AND N CENTRAL CARIBBEAN WILL DIMINISH AS IRENE MOVES N. SURFACE RIDGE WILL BUILD SW ACROSS N CARIBBEAN SUN TO BRING A RETURN OF E TRADE WINDS E OF 75W. ATLANTIC OCEAN... THE PRIMARY CONCERN THIS MORNING CONTINUES TO HURRICANE IRENE CENTERED OVER THE TURKS AND CAICOS MOVING TOWARD THE S BAHAMAS...SEE SPECIAL FEATURES ABOVE. A SHORTWAVE UPPER TROUGH EXTENDS FROM AN UPPER LOW OFF THE SOUTH CAROLINA COAST NEAR NEAR 32N78W ACROSS NE FLORIDA BETWEEN JACKSONVILLE AND TALLAHASSEE GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS WITHIN 75 NM OF LINE FROM THE FLORIDA COAST NEAR VERO BEACH ALONG 30N77W THEN N TO BEYOND 33N77W. THE UPPER RIDGE ASSOCIATED WITH HURRICANE IRENE COVERS THE AREA FROM S OF 30N BETWEEN 60W-76W WITH AN UPPER LOW JUST TO THE E NEAR 25N53W. THE UPPER LOW IS GENERATING ISOLATED SHOWERS FROM 20N-27N BETWEEN 50W-55W. A WEAK 1013 MB SURFACE LOW IS CENTERED IN THE E/CENTRAL ATLC NEAR 22N41W GENERATING ISOLATED SHOWERS WITHIN 60 NM OF LINE FROM 23N39W TO 24N43W. THE REMAINDER OF THE ATLC BASIN N OF 25N IS DOMINATED BY A LARGE SURFACE RIDGE ANCHORED BY A PAIR OF 1026 MB HIGHS N OF THE DISCUSSION AREA WITH A RIDGE AXIS EXTENDING THROUGH 32N54W ALONG 31N67W TO ACROSS N FLORIDA THEN WEAKENING INTO THE GULF OF MEXICO. HURRICANE IRENE IS EXPECTED TO MOVE NW ACROSS BAHAMAS TODAY THROUGH THU CONTINUING N THU NIGHT AND FRI BEFORE EXITING THE DISCUSSION AREA MOVING ON TOWARD THE CAROLINA COAST. ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ PAW/MF