000 AXNT20 KNHC 091158 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 705 AM EST MON NOV 09 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1045 UTC. ...SPECIAL FEATURES... HURRICANE IDA IS CENTERED NEAR 25.8N 88.2W AT 09/1200 UTC OR ABOUT 205 NM SSE OF THE MOUTH OF THE MISSISSIPPI RIVER AND ABOUT 285 NM SSW OF PENSACOLA FLORIDA MOVING NNW AT 14 KT. ESTIMATED MINIMUM CENTRAL PRESSURE BASED ON DATA FROM THE HURRICANE HUNTER AIRCRAFT IS 993 MB. MAXIMUM SUSTAINED WIND SPEED IS 70 KT WITH GUSTS TO 85 KT. SEE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT1/WTNT21 KNHC FOR MORE DETAILS. SCATTERED MODERATE/ISOLATED STRONG CONVECTION COVERS THE AREA FROM 26N-29N BETWEEN 84W-87W AND FROM 24N-28N BETWEEN 87W-89W. ...TROPICAL WAVES... TROPICAL WAVE IS ALONG 55W S OF 16N MOVING W NEAR 20 KT. WAVE POSITION IS BASED ON CONTINUITY AND IS MOVING BENEATH A NARROW UPPER RIDGE. NO SIGNIFICANT DEEP CONVECTION ACCOMPANIES THE WAVE. TROPICAL WAVE IS ALONG 70W S OF 17N MOVING W NEAR 15 KT. WAVE WAVE POSITION IS BASED ON CONTINUITY AND CONTINUES TO BE ILL-DEFINED AND DIFFICULT TO TRACK AS IT MOVES WESTWARD BENEATH DRY AND STABLE AIR. NO SIGNIFICANT DEEP CONVECTION ACCOMPANIES THE WAVE. ...ITCZ... THE ITCZ AXIS IS CENTERED ALONG 10N14W 7N27W 7N42W 9N52W 10N62W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS WITHIN 150 NM ALONG THE COAST OF W AFRICA FROM 7N-10N AND WITHIN 75/90 NM OF LINE FROM 6N40W TO12N38W. CLUSTERS OF SCATTERED MODERATE CONVECTION ARE WITHIN 120 NM OF LINE FROM 5N15W TO 3N30W AND WITHIN 60 NM OF 8N FROM 27W-33W. ...DISCUSSION... GULF OF MEXICO... HURRICANE IDA REMAINS THE PRIMARY CONCERN THIS MORNING FOR THE GULF OF MEXICO BUT IS BEGINNING TO LOSE ITS DEEP CONVECTION... SEE SPECIAL FEATURES ABOVE. CONVECTION ASSOCIATED WITH IDA REMAINS ENHANCED BY UPPER LEVEL DIFFLUENCE BETWEEN AN UPPER LEVEL RIDGE EXTENDING FROM THE WESTERN CARIBBEAN NORTHWARD ACROSS CUBA JUST W OF THE FLORIDA PENINSULA GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS S OF 26N E OF 86W TO OVER FLORIDA AND INTO THE STRAITS OF FLORIDA. AN UPPER LEVEL TROUGH IN THE W GULF EXTENDS FROM TEXAS NEAR 29N96W TO THE E BAY OF CAMPECHE NEAR 19N91W AND SUPPORTS A SURFACE TROUGH THAT EXTENDS FROM 26N95W ALONG 21N93W TO THE E BAY OF CAMPECHE NEAR 19N91W. WIND SHIFT REMAINS MAINLY ASSOCIATED WITH THE SURFACE TROUGH AXIS. HOWEVER...UPPER LEVEL DIFFLUENCE N OF 24N W OF 90W IS GENERATING CLUSTERS OF SCATTERED SHOWERS/ ISOLATED THUNDERSTORMS OVER THAT AREA TO INLAND OVER LOUISIANA. THE TIGHT PRESSURE GRADIENT REMAINS BETWEEN HURRICANE IDA AND THE SURFACE RIDGE OVER THE W ATLC/SE U.S. CONTINUES TO PRODUCE GALE FORCE WINDS IN THE STRAITS OF FLORIDA. CARIBBEAN SEA... AN UPPER LEVEL RIDGE ANCHORED IN THE NW CARIBBEAN NEAR 19N82W EXTENDS AND AXIS N ACROSS CUBA INTO THE E GULF OF MEXICO. THE SOUTHERN RIDGE AXIS EXTENDS S TO OVER PANAMA/COLOMBIA NEAR 9N76W PROVIDING DIFFLUENCE ALOFT TO PRODUCE SCATTERED SHOWERS/ISOLATED THUNDERSTORMS S OF A LINE FROM COLOMBIA NEAR 11N75W TO NICARAGUA NEAR 13N84W. AN UPPER TROUGH FROM THE W/CENTRAL ATLC DIPS S OVER THE E CARIBBEAN E OF 85W GIVING THE AREA NW UPPER LEVEL FLOW AND GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS N OF 17N TO OVER CUBA BETWEEN 75W-86W AND FROM 17N-20N E OF 75W TO ACROSS THE LEEWARD ISLANDS INCLUDING THE VIRGIN ISLANDS TO HISPANIOLA. PRIMARILY MODERATE SUBSIDENCE IS NOTED ON WATER VAPOR IMAGERY FROM 12N-16N WITH SOME ISOLATED SHOWERS LOW LEVEL FAST MOVING SHOWERS ARE BEING USHERED IN ON MODERATE EASTERLY TRADEWINDS. ATLANTIC OCEAN... A SURFACE RIDGE REMAINS IN CONTROL OF THE W ATLC N OF 23N W OF 60W ANCHORED BY SEVERAL SURFACE HIGHS N OF THE REGION. A STATIONARY FRONT ENTERS THE CENTRAL ATLC NEAR 32N44W EXTENDING SW ALONG 27N52W TO 23N58W WHERE IT CONTINUES AS SURFACE TROUGH TO 19N66W. THE FEATURE IS SUPPORTED ALOFT BY A UPPER LEVEL TROUGH THAT EXTENDS S INTO THE E CARIBBEAN COVERING THE AREA BETWEEN 55W-78W. JUST TO THE E IS A NARROW HIGHLY AMPLIFIED UPPER RIDGE THAT EXTENDS FROM 16N55W TO BEYOND 32N40W PROVIDING DIFFLUENCE ALOFT TO GENERATE A BROAD AREA OF SCATTERED SHOWERS/ ISOLATED THUNDERSTORMS FROM 15N-22N BETWEEN 54W-62W AND WITHIN 75 NM OF 53W FROM 23N-27N. A NARROW UPPER LEVEL TROUGH IS OVER THE E/CENTRAL ATLC EXTENDING FROM 32N35W DIPPING INTO THE TROPICS TO NEAR 13N51W AND CONTINUES TO ENHANCE CONVECTION N OF THE ITCZ. THE E ATLC IS REMAINS UNDER THE INFLUENCE OF A SURFACE RIDGE ANCHORED ON A 1031 MB HIGH ANCHORED E OF THE AZORES. $$ WALLACE