000 WTNT42 KNHC 020907 TCDAT2 HURRICANE EARL DISCUSSION NUMBER 32 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL072010 500 AM EDT THU SEP 02 2010 AN AIR FORCE RESERVE HURRICANE HUNTER AIRCRAFT REPORTED 140 KT WINDS AT 700 MB IN THE NORTHEASTERN EYEWALL. AN EYE DROPSONDE REPORTED A SURFACE PRESSURE OF 929 MB WITH A WIND OF 25 KT...SUGGESTING A CENTRAL PRESSURE NEAR 928 MB. BASED ON THIS...THE INITIAL INTENSITY IS INCREASED TO 125 KT. EARL IS LIKELY NEAR PEAK INTENSITY AT THIS TIME...AS THE EYEWALL CONVECTION IS BECOMING A LITTLE LESS ORGANIZED IN SATELLITE IMAGERY. THE INITIAL MOTION IS 330/16. THERE IS LITTLE CHANGE TO EITHER THE FORECAST PHILOSOPHY OF THE TRACK FORECAST FOR THE FIRST 48 HR. EARL SHOULD TURN NORTHWARD AND NORTH-NORTHEASTWARD AS IT ROUNDS THE END OF THE SUBTROPICAL RIDGE AND ENTERS THE WESTERLIES. THE TRACK MODEL GUIDANCE IS TIGHTLY CLUSTERED AROUND THIS SOLUTION...AND THE NEW TRACK IS DOWN THE MIDDLE OF THE CLUSTER. AFTER 48 HR...THE GUIDANCE HAS SHIFTED TO THE LEFT DUE TO CHANGES IN THE INTERACTION OF EARL WITH A STRONG WESTERLY TROUGH DURING EXTRATROPICAL TRANSITION. THE 48-72 HR TRACK HAS BEEN SHIFTED TO THE LEFT...BUT STILL LIES ON THE RIGHT SIDE OF THE GUIDANCE ENVELOPE. THE INTENSITY GUIDANCE SUGGESTS EARL SHOULD MAINTAIN ITS CURRENT INTENSITY FOR 12 HR OR SO. AFTER THAT...INCREASING VERTICAL WIND SHEAR AND MOTION OVER DECREASING SEA SURFACE TEMPERATURES SHOULD CAUSE STEADY WEAKENING. EXTRATROPICAL TRANSITION SHOULD BEGIN AT ABOUT 48 HR AND BE COMPLETE BY 72 HR...WITH THE REMNANTS OF EARL BEING ABSORBED INTO A LARGER BAROCLINIC LOW BY 96 HR. FORECAST POSITIONS AND MAX WINDS INITIAL 02/0900Z 29.3N 74.7W 125 KT 12HR VT 02/1800Z 31.7N 75.3W 125 KT 24HR VT 03/0600Z 34.8N 74.6W 115 KT 36HR VT 03/1800Z 38.1N 72.6W 100 KT 48HR VT 04/0600Z 41.6N 69.2W 85 KT 72HR VT 05/0600Z 50.5N 62.5W 50 KT...POST-TROP/EXTRATROP 96HR VT 06/0600Z...ABSORBED BY EXTRATROPICAL LOW $$ FORECASTER BEVEN