000 WTPZ42 KNHC 252031 TCDEP2 TROPICAL STORM DALILA DISCUSSION NUMBER 16 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL EP072007 200 PM PDT WED JUL 25 2007 DALILA IS WINDING DOWN FASTER THAN ANTICIPATED YESTERDAY. EVEN THOUGH THE SSTS BENEATH DALILA'S CENTER ARE ABOUT 27.5C...THE STRONG GRADIENT OF SST JUST TO THE NORTH OF THE SYSTEM IS ALLOWING DRY STABLE AIR TO BE ENTRAINED INTO THE WESTERN SEMI-CIRCLE OF THE CYCLONE'S CIRCULATION. A BLEND OF THE T AND CI DVORAK NUMBERS FROM TAFB AND SAB SUGGESTS AN INTENSITY OF 40 KT. DALILA HAS BEEN MOVING TOWARD THE NORTHWEST AT ABOUT 8 KT...DUE TO THE COMBINED INFLUENCE OF A DEEP-LAYER RIDGE TO ITS NORTHEAST AND A WEAK MID-LEVEL TROUGH TO ITS NORTHWEST. AS IT SPINS DOWN OVER THE NEXT COUPLE OF DAYS...THE CYCLONE WILL BE STEERED OFF TO THE WEST-NORTHWEST BY THE LOWER-LEVEL FLOW. THE TRACK FORECAST FOLLOWS THE CONSENSUS OF THE TIGHTLY-CLUSTERED MODEL GUIDANCE. DALILA WILL CONTINUE MOVING NORTHWEST TOMORROW AND WILL CROSS THE 26C SST ISOTHERM. ANY REMAINING CONVECTION WILL LIKELY FIZZLE AT THAT POINT AND THE CYCLONE SHOULD BECOME A REMNANT LOW IN ABOUT TWO DAYS. THIS SCENARIO CLOSELY FOLLOWS THE SHIPS AND GFDL INTENSITY GUIDANCE. DALILA MIGHT NOT BE AN IDENTIFIABLE LOW BY DAY 5...BUT A POSITION IS GIVEN JUST IN CASE. FORECAST POSITIONS AND MAX WINDS INITIAL 25/2100Z 20.1N 112.4W 40 KT 12HR VT 26/0600Z 20.8N 113.3W 35 KT 24HR VT 26/1800Z 21.7N 114.7W 30 KT 36HR VT 27/0600Z 22.3N 116.2W 30 KT 48HR VT 27/1800Z 23.0N 117.9W 25 KT...REMNANT LOW 72HR VT 28/1800Z 24.0N 120.5W 20 KT...REMNANT LOW 96HR VT 29/1800Z 24.0N 123.0W 20 KT...REMNANT LOW 120HR VT 30/1800Z 24.0N 125.0W 20 KT...REMNANT LOW $$ FORECASTER LANDSEA/AVILA