000 WTNT41 KNHC 070233 TCDAT1 TROPICAL DEPRESSION IDA DISCUSSION NUMBER 11 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL112009 1000 PM EST FRI NOV 06 2009 A 2302 UTC SSMIS MICROWAVE PASS INDICATED THAT THE LOW-LEVEL CENTER OF IDA WAS LOCATED JUST OFF THE NORTHEASTERN COAST OF HONDURAS AND WAS DISPLACED TO THE SOUTH AND SOUTHEAST OF THE DEEP CONVECTION. NEW CONVECTION IS DEVELOPING CLOSE TO THE CENTER...AND DVORAK ESTIMATES FROM TAFB AND SAB ARE 25 KT AND 30 KT...RESPECTIVELY. NOAA BUOY 42057...LOCATED ABOUT 150 N MI EAST-NORTHEAST OF THE CENTER...RECENTLY REPORTED A 1-MINUTE SUSTAINED WIND OF 35 KT...BUT IT APPEARS THAT THIS OCCURRED WITH THE PASSAGE OF A SQUALL AND MAY NOT BE REPRESENTATIVE OF THE OVERALL CIRCULATION. THEREFORE...IDA IS KEPT AS A TROPICAL DEPRESSION FOR THIS ADVISORY...BUT IT IS PROBABLY VERY CLOSE TO REGAINING TROPICAL STORM STATUS. IDA CONTINUES TO MOVE NORTHWARD AT 360/6. A MID-LEVEL ANTICYCLONE BETWEEN JAMAICA AND HISPANIOLA AND A DEEP-LAYER TROUGH OVER MEXICO ARE EXPECTED TO STEER IDA NORTH-NORTHWESTWARD THROUGH THE NEXT 72 HOURS. THE TRACK GUIDANCE IS IN GOOD AGREEMENT DURING THIS PERIOD ALTHOUGH THE GFDL AND HWRF MODELS ARE THE EASTERNMOST MODELS AND HAVE FORCED THE MODEL CONSENSUS A LITTLE MORE TO THE EAST. THE FORECAST BEYOND 72 HOURS IS STILL COMPLEX AND IS DEPENDENT ON HOW IDA INTERACTS WITH THE FRONT AND SHORTWAVE TROUGH OVER THE GULF OF MEXICO. MOST OF THE GUIDANCE SHOWS IDA BECOMING EXTRATROPICAL BY 96 HOURS ONCE IT MERGES WITH THE FRONT...BUT THE SOLUTIONS VARY ON WHERE THE LOW GOES NEXT. ONLY THE 1200 UTC ECMWF AND UKMET SHOW IDA BECOMING PICKED UP BY A SHORTWAVE TROUGH AND MOVING NORTHEASTWARD OVER THE NORTHERN GULF. THE OTHER MODELS INDICATE A MORE PRONOUNCED SOUTHWARD MOTION AFTER 96 HOURS...AND THE OFFICIAL FORECAST NOW SHOWS A SLOW SOUTHEASTWARD TURN AT 120 HOURS. ALTHOUGH WATERS ARE WARM OVER THE NORTHWESTERN CARIBBEAN...VERTICAL SHEAR IS EXPECTED TO HAMPER MUCH INTENSIFICATION OVER THE NEXT FEW DAYS. THE GFDL AND HWRF MAKE IDA A HURRICANE OVER THE CENTRAL GULF OF MEXICO...A SCENARIO THAT DOES NOT SEEM PLAUSIBLE IN THE FACE OF WESTERLY SHEAR THAT IS EXPECTED TO INCREASE TO 50 OR 60 KT BY DAY 4. THE OFFICIAL FORECAST INDICATES SOME SLOW STRENGTHENING OVER THE NEXT SEVERAL DAYS BUT PEAKS THE INTENSITY AT 45 KT...WHICH IS JUST BELOW THE INTENSITY CONSENSUS. IT IS OF NOTE THAT MOST OF THE GLOBAL MODELS ARE SHOWING A LARGE PRESSURE GRADIENT BETWEEN A HIGH OVER THE SOUTHEASTERN UNITED STATES AND THE TROPICAL CYCLONE. THIS COULD CONTRIBUTE TO A LARGE AREA OF STRONG WINDS OVER THE GULF OF MEXICO NOT DIRECTLY ATTRIBUTABLE TO IDA. FORECAST POSITIONS AND MAX WINDS INITIAL 07/0300Z 16.2N 84.0W 30 KT 12HR VT 07/1200Z 17.1N 84.2W 35 KT 24HR VT 08/0000Z 18.4N 84.8W 35 KT 36HR VT 08/1200Z 19.7N 85.5W 40 KT 48HR VT 09/0000Z 21.4N 86.5W 45 KT 72HR VT 10/0000Z 25.5N 88.0W 45 KT 96HR VT 11/0000Z 27.5N 87.0W 45 KT...EXTRATROPICAL 120HR VT 12/0000Z 26.5N 85.6W 35 KT...EXTRATROPICAL $$ FORECASTER BERG