000 AXNT20 KNHC 082359 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 705 PM EST SUN NOV 08 2009 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...METEOROLOGICAL ANALYSIS...WEATHER OBSERVATIONS...AND RADAR. BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2315 UTC. ...SPECIAL FEATURES... HURRICANE IDA IS CENTERED NEAR 23.1N 86.5W AT 09/0000 UTC OR ABOUT 120 NM WNW OF THE WESTERN TIP OF CUBA AND ABOUT 385 NM SSE OF THE MOUTH OF THE MISSISSIPPI RIVER MOVING NNW AT 10 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 979 MB. MAXIMUM SUSTAINED WIND SPEED IS 90 KT WITH GUSTS TO 110 KT. SCATTERED STRONG CONVECTION IS LOCATED WITHIN 90 NM OF THE CENTER WITH NUMEROUS MODERATE/ISOLATED STRONG CONVECTION ELSEWHERE FROM 17N-25N BETWEEN 80W-85W AND FROM 23N-27N BETWEEN 85W-88W. SEE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT1/WTNT21 KNHC FOR MORE DETAILS. ...TROPICAL WAVES... TROPICAL WAVE IS ALONG 49W S OF 18N MOVING W NEAR 15 KT. THE WAVE HAS MOVED W OF AN UPPER LEVEL AREA OF DIFFLUENCE ACROSS THE TROPICAL ATLC E OF 45W AND NOW RESIDES BENEATH A DRY UPPER LEVEL TROUGH AXIS ALONG 50W. TOTAL PRECIPITABLE WATER VALUES IN THE VICINITY OF THE WAVE AXIS HAVE LESSENED OVER THE PAST 24 HOURS...HOWEVER A BROAD AREA OF 850 MB RELATIVE VORTICITY FOLLOWS THE WAVE S OF 15N BETWEEN 40W-50W. NO SIGNIFICANT DEEP CONVECTION ACCOMPANIES THE WAVE. TROPICAL WAVE IS ALONG 68W S OF 18N MOVING W NEAR 15 KT. THE WAVE CONTINUES TO REMAIN ILL-DEFINED AND DIFFICULT TO TRACK AS IT MOVES WESTWARD BENEATH DRY AND STABLE NNW UPPER LEVEL FLOW LOCATED ACROSS MUCH OF THE CARIBBEAN SEA. ISOLATED SHOWERS CONTINUE MOVING ACROSS THE BASIN ON 10-15 KT TRADEWINDS. ...ITCZ... THE ITCZ AXIS IS CENTERED ALONG 10N14W 5N26W 8N48W 9N51W 8N60W. CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM 5N-8N BETWEEN 23W-32W. SIMILAR CONVECTION IS FROM 8N-13N BETWEEN 32W-44W AND LARGELY ENHANCED BY UPPER LEVEL DIFFLUENCE EAST OF AN UPPER TROUGH WITH AXIS ALONG 50W. ...DISCUSSION... GULF OF MEXICO... HURRICANE IDA IS LOCATED IN THE SOUTHERN GULF OF MEXICO NORTH OF THE YUCATAN CHANNEL AND REMAINS ADJACENT TO A SURFACE RIDGE LOCATED OVER THE SE CONUS...NORTHERN FLORIDA...AND W ATLC WATERS. CONVECTION ASSOCIATED WITH IDA REMAINS MAINLY S OF 27N E OF 88W ENHANCED BY UPPER LEVEL DIFFLUENCE BETWEEN AN UPPER LEVEL RIDGE EXTENDING FROM THE WESTERN CARIBBEAN NORTHWARD ACROSS CUBA AND THE FLORIDA PENINSULA AND AN UPPER LEVEL TROUGH WITH AXIS ALONG 92W POSITIONED TO THE WEST OF IDA. THE UPPER LEVEL TROUGH ALSO SUPPORTS A SURFACE TROUGH THAT EXTENDS FROM NEAR BROWNSVILLE TEXAS TO A 1008 MB LOW NEAR 23N95W THEN TO THE WESTERN YUCATAN PENINSULA NEAR 19N91W. ASIDE FROM THE WIND SHIFT ASSOCIATED WITH THE SURFACE TROUGH AXIS...UPPER LEVEL DIFFLUENCE N OF 24N W OF 88W IS GENERATING SCATTERED SHOWERS AND ISOLATED TSTMS ACROSS THE NW GULF WATERS AND INLAND OVER THE EASTERN TEXAS AND LOUISIANA GULF COAST. WITH THE INCREASED PRESSURE GRADIENT CREATED BETWEEN HURRICANE IDA...THE LOW OVER THE WESTERN GULF...AND THE SURFACE RIDGE OVER THE SE CONUS...A LARGE AREA OF EASTERLY WIND UP TO 30 KT IS LOCATED NORTH OF IDA AND ACROSS THE NW GULF. CARIBBEAN SEA... AS HURRICANE IDA MOVES INTO THE SOUTHERN GULF OF MEXICO THROUGH THE YUCATAN CHANNEL...CONVECTIVE BANDS CONTINUE TO BRING SCATTERED SHOWERS AND TSTMS TO WESTERN AND CENTRAL CUBA AND THE NW CARIBBEAN WATERS FROM 17N-23N BETWEEN 80W-85W. THIS ACTIVITY IS BEING ENHANCED BY UPPER LEVEL DIFFLUENCE ASSOCIATED WITH AN UPPER LEVEL ANTICYCLONIC CIRCULATION CENTERED IN THE SW CARIBBEAN NEAR 13N80W. UPPER LEVEL DIFFLUENCE IS ALSO LOCATED OVER THE SW CARIBBEAN AND IS PRODUCING SCATTERED SHOWERS AND ISOLATED TSTMS S OF 13N BETWEEN 75W-85W. ELSEWHERE E OF 80W... N-NW UPPER LEVEL FLOW DOMINATES OVER THE BASIN WITH PRIMARILY MODERATE SUBSIDENCE NOTED ON WATER VAPOR IMAGERY FROM 11N-17N. A FEW ISOLATED SHOWERS ARE MOVING WESTWARD ON 10-15 KT TRADEWINDS IN THE VICINITY OF THE TROPICAL WAVE ALONG 68W AND N OF 17N ACROSS HISPANIOLA...PUERTO RICO...AND THE US/UK VIRGIN ISLANDS THIS EVENING. ATLANTIC OCEAN... A SURFACE RIDGE CONTROLS THE W ATLC N OF 24N W OF 60W ANCHORED BY A 1026 MB HIGH CENTERED NORTH OF THE DISCUSSION AREA NEAR 35N74W. FARTHER EAST...A COLD FRONT ENTERS THE REGION NEAR 32N46W AND EXTENDS SW ALONG 29N50W TO 22N60W. THE FRONT IS SUPPORTED ALOFT BY A SHARP UPPER LEVEL TROUGH WITH AXIS FROM 30N61W TO 22N66W. EAST OF THIS UPPER LEVEL TROUGH...LOW-LEVEL CONVERGENCE NEAR THE FRONT COUPLED WITH UPPER LEVEL DIFFLUENCE IS GENERATING A BROAD AREA OF SCATTERED SHOWERS AND ISOLATED TSTMS WITHIN 200 NM SE OF THE FRONT AND WITHIN 300 NM NW OF THE FRONT. AN AREA OF SCATTERED SHOWERS TRAILS WEST FROM THE TAIL END OF THE COLD FRONT ALONG 20N BETWEEN 60W-72W. SCATTERED SHOWERS ARE FROM HISPANIOLA...PUERTO RICO...AND THE US/UK VIRGIN ISLANDS TO 22N. THE EASTERN ATLC IS UNDER THE INFLUENCE OF A SURFACE RIDGE ANCHORED ON A 1030 MB HIGH CENTERED EAST OF THE AZORES NEAR 38N21W. AN UPPER LEVEL TROUGH IS OVER THE E/CENTRAL ATLC EXTENDING AN AXIS ALONG 50W DIPPING TO NORTHERN SOUTH AMERICA NEAR SURINAME AND CONTINUES TO ENHANCE CONVECTION N OF THE ITCZ AXIS FROM 9N-20N BETWEEN 32W-42W. $$ HUFFMAN