000 WTPZ44 KNHC 252047 TCDEP4 HURRICANE CELIA DISCUSSION NUMBER 27 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL EP042010 200 PM PDT FRI JUN 25 2010 SATELLITE IMAGERY INDICATES THAT CELIA HAS WEAKENED THIS AFTERNOON. ENHANCED INFRARED IMAGES SHOW SIGNIFICANT WARMING OF THE EYEWALL CONVECTION...AND THE EYE DIAMETER HAS INCREASED TO 25 N MI. CONSEQUENTLY...THE INITIAL INTENSITY IS LOWERED TO 115 KT...AND IS BASED ON A CONSENSUS OF DVORAK SATELLITE INTENSITY ESTIMATES FROM TAFB AND SAB...AND AN ADVANCED OBJECTIVE DVORAK TECHNIQUE ESTIMATE OF 115 KT. CELIA IS FORECAST TO CONTINUE ON A WEAKENING TREND AND DECAY TO A REMNANT LOW BY DAY 4...AS THE SYSTEM MOVES OVER COOLER WATER AND INTO A LESS THAN FAVORABLE THERMODYNAMIC ENVIRONMENT. THE SHIPS AND LGEM INTENSITY MODELS REFLECT THIS SCENARIO AND SERVE AS A BASIS FOR THE OFFICIAL INTENSITY FORECAST. THE INITIAL MOTION IS ESTIMATED AT 295/10...WITHIN THE EAST- SOUTHEASTERLY MID TO UPPER-LEVEL FLOW OF A RIDGE TO THE NORTH OF THE CYCLONE. LARGE-SCALE AND REGIONAL MODELS INDICATE THAT THE RIDGE WILL MAINTAIN ITS STRENGTH DURING THE NEXT 36 HOURS... ALLOWING CELIA TO CONTINUE ON A GENERAL WEST-NORTHWESTWARD MOTION. FOR THE REMAINDER OF THE FORECAST PERIOD...MODELS SUGGEST THAT THE RIDGE WILL WEAKEN IN RESPONSE TO A MID-LEVEL TROUGH APPROACHING THE CALIFORNIA COAST. THIS CHANGE IN THE SYNOPTIC STEERING PATTERN IS EXPECTED TO INDUCE A REDUCTION IN FORWARD SPEED AS THE SYSTEM SPINS DOWN TO A REMNANT LOW. THE NHC FORECAST IS AN UPDATE OF THE PREVIOUS ADVISORY AND IS BASED ON A BLEND OF THE DYNAMICAL MULTI-MODEL CONSENSUS. FORECAST POSITIONS AND MAX WINDS INITIAL 25/2100Z 14.2N 119.0W 115 KT 12HR VT 26/0600Z 14.9N 120.4W 90 KT 24HR VT 26/1800Z 15.6N 122.0W 70 KT 36HR VT 27/0600Z 16.0N 123.3W 60 KT 48HR VT 27/1800Z 16.2N 124.3W 45 KT 72HR VT 28/1800Z 16.4N 125.3W 30 KT 96HR VT 29/1800Z 16.5N 126.0W 25 KT...POST-TROP/REMNT LOW 120HR VT 30/1800Z 16.5N 126.5W 25 KT...POST-TROP/REMNT LOW $$ FORECASTER ROBERTS/AVILA