000 WTNT42 KNHC 040244 TCDAT2 TROPICAL STORM KAREN DISCUSSION NUMBER 4 NWS NATIONAL HURRICANE CENTER MIAMI FL AL122013 1000 PM CDT THU OCT 03 2013 KAREN CONTINUES TO BE A SHEARED CYCLONE WITH A VIGOROUS CIRCULATION...AND WITH MOST OF THE THUNDERSTORM ACTIVITY TO THE NORTH AND EAST OF THE CENTER. THERE HAS BEEN AN EXCELLENT COVERAGE BY BOTH AIR FORCE AND NOAA HURRICANE HUNTER PLANES DURING THE PAST SEVERAL HOURS. BASED ON THAT RECONNAISSANCE DATA...THE INITIAL INTENSITY IS KEPT AT 55 KNOTS IN THIS ADVISORY. THE SHEAR AFFECTING KAREN IS FORECAST TO INCREASE AND THIS WOULD SUGGEST WEAKENING. IT IS BECOMING LESS REALISTIC THAT KAREN WILL BECOME A HURRICANE IN A DAY OR TWO...BUT GIVING CREDIT TO SOME DYNAMICAL MODELS...LIKE THE HWRF...WHICH DO SO...THE NHC FORECAST CALLS FOR A SLIGHT STRENGTHENING. IT IS ANTICIPATED THAT KAREN WILL BE ON A WEAKENING TREND BEYOND 48 HOURS...AND BECOME EXTRATROPICAL BY DAY 4. FIXES FROM THE HURRICANE HUNTER PLANES INDICATE THAT KAREN IS MOVING TOWARD THE NORTH-NORTHWEST OR 335 DEGREES AT 9 KNOTS. AS A NARROW RIDGE OVER FLORIDA WEAKENS OR SLIDES EASTWARD...AND A LARGE MID- TO UPPER-LEVEL TROUGH APPROACHES FROM THE WEST...THE CYCLONE WILL BEGIN TO MOVE SLOWLY NORTHWARD AND THEN RECURVE TO THE NORTHEAST WITH AN INCREASE IN FORWARD SPEED. THE OVERALL TRACK GUIDANCE SUGGESTS A TYPICAL RECURVATURE OVER THE CENTRAL GULF OF MEXICO AND SO DOES THE NHC FORECAST. IN FACT...THE OFFICIAL FORECAST IS VERY SIMILAR TO THE PREVIOUS ONE...AND FOLLOWS VERY CLOSELY THE MULTI-MODEL CONSENSUS. GIVEN THE CURRENT NHC FORECAST...NO CHANGE IN WATCHES AND WARNINGS IS NECESSARY AT THIS TIME...BUT THIS WILL BE REVISITED AS KAREN PROGRESSES NORTHWARD ACROSS THE CENTRAL GULF OF MEXICO. FORECAST POSITIONS AND MAX WINDS INIT 04/0300Z 24.2N 89.0W 55 KT 65 MPH 12H 04/1200Z 25.5N 89.7W 55 KT 65 MPH 24H 05/0000Z 26.9N 90.0W 60 KT 70 MPH 36H 05/1200Z 28.0N 90.0W 60 KT 70 MPH 48H 06/0000Z 29.2N 89.0W 60 KT 70 MPH 72H 07/0000Z 32.5N 84.5W 35 KT 40 MPH...INLAND 96H 08/0000Z 36.5N 79.5W 25 KT 30 MPH...POST-TROP/EXTRATROP 120H 09/0000Z...DISSIPATED $$ FORECASTER AVILA