000 WTNT42 KNHC 291439 TCDAT2 SUBTROPICAL STORM LAURA DISCUSSION NUMBER 2 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL122008 1100 AM EDT MON SEP 29 2008 AN 0852 UTC QUIKSCAT PASS OVER LAURA CONFIRMED THAT THE MAXIMUM WINDS ARE NEAR 50 KT WITHIN A SWATH LOCATED ABOUT 75 NM EAST OF THE CENTER. SUBTROPICAL CLASSIFICATIONS OF ST3.0 FROM TAFB AND SAB ALSO SUPPORT THIS INITIAL INTENSITY. A PRONOUNCED CONVECTIVE BAND NOW CURLS ABOUT THREE QUARTERS OF THE WAY AROUND THE EAST AND NORTH OF THE LARGE CIRCULATION BUT THE LOW-LEVEL CENTER REMAINS BROAD AND ILL-DEFINED WITH SEVERAL INTERNAL SMALLER SWIRLS. WITH THE IMPROVED CONVECTIVE SIGNATURE...A CASE COULD BE MADE THAT THE CYCLONE IS BEGINNING TO ACQUIRE MORE TROPICAL CHARACTERISTICS. LAURA IS BEGINNING TO MAKE A MORE PRONOUNCED POLEWARD TURN AS IT MOVES BETWEEN HIGH PRESSURE NORTH OF THE AZORES AND THE EXTRATROPICAL REMNANTS OF HURRICANE KYLE OVER THE CANADIAN MARITIMES. A NORTHWESTWARD TO NORTHWARD MOTION WILL CONTINUE FOR THE NEXT 36 HOURS OR SO BUT THE LATEST TRACK GUIDANCE HAS SHIFTED TO THE RIGHT OF THE PREVIOUS OFFICIAL FORECAST. THE NEW FORECAST DOES NOT GO AS FAR TO THE RIGHT AS THE MODEL CONSENSUS AND INSTEAD LIES ON THE LEFT SIDE OF THE GUIDANCE...CLOSE TO THE GFS AND GFDL. LAURA WILL LIKELY BE PICKED UP BY THE MID-LATITUDE TROUGH CURRENTLY OVER THE CANADIAN MARITIMES BY DAY 3 AND THEN ACCELERATE EASTWARD WITHIN THE MID-LATITUDE FLOW...POSSIBLY APPROACHING THE BRITISH ISLES AS A POWERFUL EXTRATROPICAL LOW. OCEAN WATERS ARE MARGINALLY WARM NEAR LAURA...BUT APPEAR TO BE JUST WARM ENOUGH TO SUPPORT INCREASED CONVECTION. IF THE CONVECTION CAN WRAP CLOSER TO THE CENTER...THERE IS A CHANCE THAT THE CYCLONE COULD BECOME A TROPICAL CYCLONE BEFORE TRANSITIONING INTO AN EXTRATROPICAL LOW. THEREFORE...SOME STRENGTHENING IS INDICATED OVER THE NEXT 24 HOURS JUST BEFORE LAURA MOVES OVER INCREASINGLY LOWER SEA SURFACE TEMPERATURES. MOST OF THE DYNAMICAL GUIDANCE IS RATHER UNIMPRESSED WITH THE POTENTIAL FOR INTENSIFICATION WHEREAS THE SHIPS MODEL SHOWS LAURA STRENGTHENING TO 80 KT BY DAY 4 OR 5...PRIMARILY DUE TO A STRONG CONTRIBUTION FROM COLD UPPER LEVEL TEMPERATURES. FORECAST POSITIONS AND MAX WINDS INITIAL 29/1500Z 37.4N 47.8W 50 KT 12HR VT 30/0000Z 38.1N 48.3W 55 KT 24HR VT 30/1200Z 39.8N 48.3W 60 KT 36HR VT 01/0000Z 41.8N 47.7W 60 KT 48HR VT 01/1200Z 44.4N 46.6W 55 KT...EXTRATROPICAL 72HR VT 02/1200Z 51.5N 41.5W 50 KT...EXTRATROPICAL 96HR VT 03/1200Z 55.5N 30.5W 45 KT...EXTRATROPICAL 120HR VT 04/1200Z 55.0N 15.0W 45 KT...EXTRATROPICAL $$ FORECASTER BERG/PASCH