000 WTPZ42 KNHC 242054 TCDEP2 TROPICAL STORM DALILA DISCUSSION NUMBER 12 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL EP072007 ISSUED BY THE HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD 200 PM PDT TUE JUL 24 2007 LATEST CONVENTIONAL SATELLITE IMAGERY INDICATES THAT DALILA CONTINUES TO GRADUALLY STRENGTHEN DESPITE MOST OF THE DEEP CONVECTION BEING DISPLACED SOUTH OF THE CENTER. THE CURRENT INTENSITY HAS BEEN INCREASED TO 50 KTS BASED ON A CONSENSUS OF THE SUBJECTIVE DVORAK ESTIMATES FROM TAFB AND SAB. VISIBILE...IR...AND MICROWAVE SATELLITE IMAGERY NOW SUGGEST THAT THE BROAD CIRCULATION CENTER OF DALILA WAS NOT AS FAR WEST AS EARLIER THOUGHT. THE NUMERICAL GUIDANCE HAS COME INTO SLIGHTLY BETTER AGREEMENT SINCE THIS MORNING...BUT DIFFERENCES REMAIN ABOUT HOW A TROUGH TO THE NORTH OF DALILA WILL INFLUENCE ITS TRACK. A WEAKENING IN THE RIDGE OVER MEXICO HAS ALLOWED DALILA TO MOVE NORTH DURING THE DAY. THE CURRENT FORECAST ALLOWS THE NORTHWARD TREND TO CONTINUE FOR ABOUT 12 HOURS OR SO BEFORE STARTING TO CURVE THE STORM TO THE WEST IN A FASHION SIMILAR TO THE GFS. THE ECMWF AND CANADIAN STILL ALLOW FOR A MORE NORTHERLY TRACK IN RESPONSE TO AN ANOMALOUSLY STRONG SECOND SHORTWAVE TROUGH THAT PASSES TO THE NORTH OF DALILA. THE WAY THE GFS AND GFDL HANDLE THIS SECOND TROUGH IS PREFERRED OVER THE ECMWF/CANADIAN SOLUTION. VERTICAL SHEAR IS CURRENTLY AROUND 16 KNOTS OR SO...BUT IT IS EXPECTED TO DECREASE TO AROUND 5 OT 6 KNOTS IN THE NEXT 24 TO 48 HOURS. GIVEN THE DECREASING SHEAR...WE WOULD EXPECT THE STORM WILL BE ABLE TO STRENGTHEN TO AROUND 60 KTS BY 36 HOURS. THE STORM SHOULD WEAKEN AFTER THAT ONCE IT ENCOUNTERS COOLER SEA SURFACE TEMPERATURES. FORECAST POSITIONS AND MAX WINDS INITIAL 24/2100Z 17.3N 110.2W 50 KT 12HR VT 25/0600Z 18.2N 110.7W 55 KT 24HR VT 25/1800Z 19.0N 111.4W 55 KT 36HR VT 26/0600Z 19.8N 112.6W 60 KT 48HR VT 26/1800Z 20.5N 113.8W 55 KT 72HR VT 27/1800Z 21.8N 116.5W 45 KT 96HR VT 28/1800Z 22.8N 119.3W 30 KT 120HR VT 29/1800Z 23.6N 122.1W 20 KT...DISSIPATING $$ FORECASTER BANN