000 AXNT20 KNHC 231153 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT TUE AUG 23 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 20.6N 70.7W AT 23/1200 UTC OR ABOUT 70 MI...110 KM SSE OF GRAND TURK ISLAND...OR ABOUT 55 MI...90 KM N OF PUERTO PLATA DOMINICAN REPUBLIC MOVING WNW AT 10 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 978 MB. MAXIMUM SUSTAINED WIND SPEED IS 85 KT WITH GUSTS TO 105 KT MAKING IRENE A CATEGORY TWO HURRICANE. 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 PERSISTS FROM THE NORTH COAST OF HISPANIOLA TO 21N BETWEEN 69W-72W. A BAND OF STRONG CONVECTION IS ALSO NOTED FROM 17N TO THE SOUTHERN COAST OF DOMINICAN REPUBLIC 68W AND 70W. BANDS OF SHOWERS CONTINUE TO PUSH N AGAINST THE CENTRAL HIGHLANDS IN PUERTO RICO AS WELL AS ACROSS THE US AND BRITISH VIRGIN ISLANDS. HURRICANE FORCE WINDS EXTEND OUTWARD UP TO 40 NM FROM THE CENTER AND TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 160 NM TO THE NE OF THE CENTER. ...THE ITCZ/THE MONSOON TROUGH... THE MONSOON TROUGH IS ANALYZED ACROSS AFRICA ENTERING THE E TROPICAL ATLC NEAR A 1006 MB LOW NEAR DAKAR SENEGAL ALONG 13N18W TO 12N24W TO 14N30W. NO MONSOON TROF OR ITCZ ARE NOTED IN A LIGHT WINDS PATTERN EVIDENT BETWEEN 30W AND 40W...S OF A LOW PRES AREA NEAR 21N35W. AN ITCZ IS NOTED FROM 12N41W TO 15N60W. ...DISCUSSION... GULF OF MEXICO... BROAD UPPER RIDGE CONTINUES TO DOMINATE THE GULF ANCHORED OVER CENTRAL TEXAS. A LIGHT PRES PATTERN REMAINS IN PLACE OVER THE ENTIRE GULF THIS MORNING...WITH SURFACE WINDS GENERALLY 5 TO 10 KT IN E TO SE FLOW OVER THE WESTERN GULF AND NE TO E WINDS OVER THE EASTERN GULF. SEAS REMAIN 1 TO 3 FT. THE EXCEPTION REMAINS OVER THE STRAITS OF FLORIDA WHERE WINDS ARE 15 TO 20 KT IN E FLOW...ENHANCED IN PART BY THE APPROACH OF HURRICANE IRENE INTO THE SOUTHERN BAHAMAS. A FEW SHOWERS AND TSTMS ARE NOTED OVER THE SE GULF...W OF THE FLORIDA KEYS AND N OF WESTERN CUBA...THE RESULT OF THE ENHANCED SURFACE FLOW AND WEAK DIVERGENCE ALOFT AT THE BASE OF AN UPPER TROUGH DIGGING THROUGH THE EASTERN UNITED STATES. HURRICANE IRENE CURRENTLY N OF MONA PASSAGE/E DOMINICAN REPUBLIC IS FORECAST TO TRACK NW JUST N OF HISPANIOLA TONIGHT THEN ACROSS BAHAMAS TUE AND WED WITH TROPICAL STORM CONDITIONS NOT CURRENTLY EXPECTED IN THE GULF WATERS. CARIBBEAN SEA... PRIMARY CONCERN THIS EVENING CONTINUES TO BE HURRICANE IRENE CENTERED N OF HISPANIOLA. THE PROXIMITY OF IRENE IS KEEPING MODERATE TO FRESH WINDS IN PLACE ALONG SCATTERED TO NUMEROUS SHOWERS AND TSTMS IN PLACE OVER THE NE CARIBBEAN WATERS...N OF 15N E OF 75W. NE WINDS ARE INCREASING TO 20 KT THROUGH THE WINDWARD PASSAGE AS WELL. LIGHT TO MODERATE NE WINDS COVER THE REMAINDER OF THE WESTERN CARIBBEAN. SCATTERED SHOWERS AND ISOLATED TSTMS ARE NOTED OVER THE FAR NW CARIBBEAN NEAR THE YUCATAN CHANNEL IN RESPONSE TO DIVERGENCE ASSOCIATED WITH AN INVERTED UPPER TROUGH EXTENDING FROM WESTERN CUBA THROUGH HONDURAS. CONVECTION IS LIMITED ELSEWHERE IN THE CARIBBEAN DUE TO SUBSIDENCE ON THE PERIPHERY OF IRENE. HURRICANE IRENE IS FORECAST TO MOVE JUST N OF HISPANIOLA TONIGHT THROUGH THIS EVENING. ATLANTIC OCEAN... THE PRIMARY CONCERN THIS EVENING CONTINUES TO HURRICANE IRENE CENTERED N OF HISPANIOLA. A SURFACE RIDGE EXTENDS FROM ROUGHLY 31N50W TO CENTRAL FLORIDA. ASCAT DATA SHOW WINDS OF 20 TO 30 KT FROM N OF THE LEEWARD ISLAND NEAR 19N TO 25N BETWEEN 60W AND 70W...BETWEEN IRENE THE RIDGING TO THE NORTH. SCATTERED SHOWERS AND TSTMS ARE NOTED IN THE CAY SAL AREA OF THE BAHAMAS...DUE TO ENHANCED MODERATE TO FRESH SURFACE LOW AND DIVERGENCE ALOFT AT THE BASE OF AN UPPER TROUGH DIGGING THROUGH THE SE UNITED STATES. FURTHER E...BROAD LOW LEVEL TROUGHING IS NOTED ON GOES HIGH DENSITY WIND OUTPUT...TO THE SE OF AN UPPER TROUGH NEAR 18N50W. SUBSIDENT DRY AIR TO THE W OF THE UPPER LOW IS INHIBITING CONVECTION FROM THE LEEWARD ISLANDS TO 50W. A 1012 MB SURFACE LOW IS NOTED NEAR 21N35W. DESPITE THIS BEING A FAIRLY WEAK LOW...THE GRADIENT REMAINS TIGHT AGAINST HIGH PRES OVER THE N CENTRAL ATLC...ALLOWING FRESH E WINDS TO THE N OF THE LOW...ALONG WITH SCATTERED MODERATE CONVECTION WITHIN 120 NM NE QUADRANT OF THE LOW. FURTHER E...AN ACTIVE LOW PRES AREA REMAINS OFF THE COAST OF SENEGAL NEAR 14N21W...WITH SCATTERED MODERATE TO ISOLATED STRONG CONVECTION NOTED WITHIN 120 NM N SEMICIRCLE. ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ CHRISTENSEN