Tropical Storm EMILIA
ZCZC MIATCDEP1 ALL TTAA00 KNHC DDHHMM TROPICAL STORM EMILIA DISCUSSION NUMBER 12 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL EP062006 200 AM PDT MON JUL 24 2006 INFRARED SATELLITE IMAGERY SHOWS THAT THERE HAS BEEN LITTLE CHANGE IN THE ORGANIZATION OF EMILIA OVER THE LAST SEVERAL HOURS. ACCORDINGLY...THE INITIAL INTENSITY REMAINS AT 60 KT BASED ON CONSENSUS SATELLITE INTENSITY ESTIMATES FROM ALL THREE AGENCIES. EMILIA IS EXPECTED TO REMAIN OVER WARM WATERS FOR THE NEXT 24 TO 36 HOURS. ADDITIONALLY...DYNAMICAL MODELS SUGGEST THAT UPPER LEVEL OUTFLOW WILL INCREASE TO THE NORTH OF THE CYCLONE AND WATER VAPOR IMAGERY INDICATES THIS MAY ALREADY BE TAKING PLACE. ACCORDINGLY... THE OFFICIAL FORECAST CALLS FOR SOME INTENSIFICATION DURING THE NEXT 24-36 HOURS. THEREAFTER...THE WINDOW OF OPPORTUNITY FOR STRENGTHENING SHUTS AS THE CYCLONE IS EXPECTED TO MOVE OVER PROGRESSIVELY COOLER WATERS AND ENCOUNTER A MORE STABLE AIRMASS. THESE TWO NEGATIVE FACTORS SHOULD BRING ABOUT RAPID WEAKENING WITH EMILIA EXPECTED TO BECOME A REMNANT LOW BY 96 HOURS AND DISSIPATE BY 120 HOURS. IT SHOULD BE NOTED THAT INTENSITY GUIDANCE HAS BEEN TRENDING WEAKER BUT THE OFFICIAL FORECAST MAINTAINS CONTINUITY BASED ON THE INCREASING OUTFLOW. THE INITIAL MOTION CONTINUES TO BE WEST-NORTHWESTWARD OR 285/8. THE STEERING IS DOMINATED BY A STRONG DEEP-LAYERED RIDGE OVER THE SOUTHWESTERN UNITED STATES. MOST OF THE DYNAMICAL MODELS INDICATE THAT EMILIA WILL GRADUALLY TURN MORE NORTHWESTWARD DURING THE NEXT 24 HOURS AS THE CYCLONE REACHES THE SOUTHWESTERN PERIPHERY OF THIS RIDGE. AN ALTERNATIVE SOLUTION IS PROVIDED BY THE GFDL AND CANADIAN MODELS WHICH SHOW A MORE NORTHWARD MOTION DUE TO A STRONGER MID-LEVEL RIDGE CURRENTLY EXTENDING ACROSS CENTRAL AMERICA INTO THE EASTERN PACIFIC SOUTHEAST OF EMILIA. HOWEVER...BOTH OF THESE MODELS FAIL TO SHOW THE CURRENT WEST-NORTHWESTWARD MOTION SO IT IS ASSUMED THAT THE LATTER RIDGE IS ALREADY TOO STRONG WITHIN THESE MODELS. THE OFFICIAL FORECAST IS BASED ON A CONSENSUS OF THE REMAINING GUIDANCE AND IS ESSENTIALLY UNCHANGED FROM THE PREVIOUS ADVISORY. FORECAST POSITIONS AND MAX WINDS INITIAL 24/0900Z 18.4N 109.7W 60 KT 12HR VT 24/1800Z 18.8N 110.8W 65 KT 24HR VT 25/0600Z 19.8N 112.3W 80 KT 36HR VT 25/1800Z 20.8N 113.7W 80 KT 48HR VT 26/0600Z 21.8N 115.0W 65 KT 72HR VT 27/0600Z 23.8N 118.0W 40 KT 96HR VT 28/0600Z 25.5N 121.0W 25 KT...REMNANT LOW 120HR VT 29/0600Z...DISSIPATED $$ FORECASTER RHOME/PASCH NNNN