000 AXNT20 KNHC 261746 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT MON SEP 26 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1715 UTC. ...SPECIAL FEATURES... TROPICAL STORM PHILIPPE IS CENTERED NEAR 15.2N 34.2W AT 26/1500 UTC OR ABOUT 590 NM W OF THE CAPE VERDE ISLANDS MOVING NW AT 10 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 997 MB. MAXIMUM SUSTAINED WIND SPEED IS 50 KT WITH GUSTS TO 60 KT. SCATTERED MODERATE CONVECTION REMAINS CLUSTERED NEAR THE CENTER OF PHILIPPE FROM 10N-16N BETWEEN 31W-36W. SEE LATEST NHC FORECAST/ ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT2/WTNT22 KNHC FOR MORE DETAILS. THE REMNANTS OF OPHELIA WHICH ARE ANALYZED AS A 1011 MB LOW CENTERED E-NE OF THE LEEWARD ISLANDS NEAR 18N58W. A SURFACE TROUGH EXTENDS WESTWARD FROM THE LOW CENTER TO 16N65W MORE AS A LOW-LEVEL CONVERGENCE BOUNDARY OF FLOW INTO THE LOW CENTER WHICH IS PROVIDING FOCUS FOR ISOLATED SHOWERS AND TSTMS WITHIN 120 NM S OF THE BOUNDARY. FURTHERMORE...CLOSER TO THE LOW CENTER... SCATTERED MODERATE AND ISOLATED STRONG CONVECTION IS FROM 15N-21N BETWEEN 55W-61W. THE LOW IS FORECAST TO LINGER NE OF THE LEEWARD ISLANDS AND SLOWLY DRIFT W-NW OVER THE NEXT FEW DAYS. ...TROPICAL WAVES... TROPICAL WAVE IS ANALYZED FROM 11N45W TO 17N46W MOVING W AT 5-10 KT. THE WAVE CONTINUES TO EXHIBIT WEAK LOW-LEVEL CYCLONIC TURNING IN THE VICINITY OF THE WAVE AXIS AS NOTED IN THE CLOUD FIELD SURROUNDING THE WAVE...HOWEVER...VERY DRY AIR ALOFT DUE TO NORTHWESTERLY UPPER LEVEL FLOW CONTINUES TO SUPPRESS ANY SIGNIFICANT DEEP CONVECTION. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 14N17W ALONG 11N20W TO 11N25W. WIDELY SCATTERED MODERATE CONVECTION IS FROM 04N-09N BETWEEN 21W-26W...AND FROM 10N-16N BETWEEN 23W-26W. ...DISCUSSION... GULF OF MEXICO... UPPER LEVEL WESTERLY FLOW DOMINATES ACROSS THE GULF THIS AFTERNOON BETWEEN A VIGOROUS UPPER LEVEL LOW CENTERED OVER THE GREAT LAKES REGION AND AN ANTICYCLONIC CIRCULATION CENTERED OVER SOUTHERN MEXICO NEAR 18N91W. WATER VAPOR IMAGERY INDICATES A DRY AIRMASS IS IN PLACE ACROSS MUCH OF THE GULF W OF 85W. E OF 85W ALOFT...MIDDLE TO UPPER LEVEL MOISTURE CONTINUES TO ADVECT NORTHWARD AMID A DIFFLUENT PATTERN ALOFT SE OF THE UPPER LEVEL LOW. THIS UPPER LEVEL PATTERN ALONG WITH A WEAK SURFACE TROUGH ANALYZED FROM 26N84W TO 30N84W IS PROVIDING FOCUS FOR SCATTERED SHOWERS AND TSTMS N OF 24N E OF 85W...INCLUDING PORTIONS OF THE FLORIDA PENINSULA. THE REMAINDER OF THE GULF IS UNDER CLEAR SKIES AND FAIR WEATHER CONDITIONS AS GENERALLY SE TO S WINDS ARE EXPECTED TO PERSIST OVER THE WESTERN GULF THROUGH TUESDAY. CARIBBEAN SEA... AN UPPER LEVEL ANTICYCLONIC CIRCULATION IS CENTERED OVER SOUTHERN MEXICO NEAR 18N91W AND IS PROVIDING MUCH OF THE WESTERN CARIBBEAN W OF 76W WITH NORTHEASTERLY FLOW ALOFT. THIS IN TURN IS MAINTAINING FAIR WEATHER CONDITIONS AND MOSTLY CLEAR SKIES N OF 16N W OF 76W. S OF 16N ACROSS THE SW CARIBBEAN...A PORTION OF THE E PACIFIC MONSOON TROUGH EXTENDS FROM NORTHERN COSTA RICA NEAR 10N83W TO 12N74W. LOW-LEVEL CYCLONIC FLOW AND MIDDLE TO UPPER LEVEL LIFT PROVIDED BY AN UPPER LEVEL TROUGH AXIS ALONG 14N BETWEEN 70W-80W IS GENERATING SCATTERED TO NUMEROUS SHOWERS AND SCATTERED STRONG TSTMS FROM 10N-15N BETWEEN 73W-79W. THE REMAINDER OF THE EASTERN CARIBBEAN FALLS UNDER THE INFLUENCE OF THE REMNANTS OF OPHELIA WHICH ARE ANALYZED AS A 1011 MB LOW CENTERED E-NE OF THE LEEWARD ISLANDS NEAR 18N58W AND ARE NOTED ABOVE IN THE SPECIAL FEATURES SECTION. ATLANTIC OCEAN... A NARROW UPPER LEVEL RIDGE EXTENDS FROM THE NW CARIBBEAN OVER THE FLORIDA STRAITS TO 32N76W. THIS RIDGE AXIS LIES EAST OF A VIGOROUS UPPER LEVEL LOW CENTERED OVER THE GREAT LAKES REGION. SOUTHWESTERLY UPPER LEVEL LOW BETWEEN THESE TWO UPPER LEVEL FEATURES IS ADVECTING TROPICAL MOISTURE NORTHWARD ACROSS MUCH OF THE FLORIDA PENINSULA AND FAR SW NORTH ATLC WATERS GENERATING SCATTERED SHOWERS AND TSTMS W OF A LINE FROM 23N78W TO 32N76W. THE REMAINDER OF THE SW NORTH ATLC IS UNDER THE INFLUENCE OF A RIDGE ANCHORED BY A 1021 MB HIGH CENTERED NEAR BERMUDA. HOWEVER ALOFT...AN ELONGATED UPPER LEVEL LOW IS CENTERED NEAR 25N71W AND CONTINUES TO ADVECT TROPICAL MOISTURE NORTHWARD TO 30N BETWEEN 63W-71W. SCATTERED SHOWERS AND ISOLATED TSTMS ARE RESULTING FROM UPPER LEVEL DIFFLUENT FLOW FROM 21N-26N BETWEEN 63W-71W. THE ONLY REMAINING AREA OF ACTIVE WEATHER WITHIN THE OFFSHORE ZONES IS THE REMNANTS OF OPHELIA FOCUSED AROUND A 1011 MB LOW CENTERED NEAR 18N58W. SCATTERED SHOWERS AND ISOLATED TSTMS CONTINUE TO REMAIN DISORGANIZED NEAR THE LOW OCCURRING FROM 15N-21N BETWEEN 53W-61W. FINALLY...AN UPPER LEVEL TROUGH AXIS DIPS INTO THE DISCUSSION AREA ALONG 32N37W TO 25N42W TO 22N51W ACROSS THE CENTRAL ATLC AND SUPPORTS A COLD FRONT ANALYZED FROM 32N35W 27N38W 24N46W TO 26N54W. ISOLATED SHOWERS ARE OCCURRING WITHIN 120 NM OF THE FRONT N OF 23N AND WITHIN 150 NM E OF THE FRONT N OF 30N. PRE-FRONTAL DYNAMICS WELL EAST OF THE FRONT ARE GENERATING SCATTERED SHOWERS AND ISOLATED TSTMS N OF 26N BETWEEN 26W-32W. THE REMAINDER OF THE EASTERN ATLC IS UNDER THE INFLUENCE OF A SURFACE RIDGE ANCHORED BY A 1022 MB HIGH CENTERED SE OF THE IBERIAN PENINSULA NEAR 35N13W. THE RIDGE AXIS EXTENDS FROM THE HIGH S-SW OVER THE CANARY ISLANDS TO NORTH OF THE CAPE VERDE ISLANDS NEAR 20N28W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ HUFFMAN