000 WTPZ43 KNHC 020840 TCDEP3 TROPICAL STORM ERICK DISCUSSION NUMBER 7 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL EP082007 200 AM PDT THU AUG 02 2007 LOCATING THE LOW-LEVEL CIRCULATION OF ERICK HAS BEEN QUITE A CHALLENGE EARLY THIS MORNING. ANALYSIS OF A 0249 UTC QSCT PASS ESTIMATED A CENTER ALIGNED WITH THE PREVIOUS ADVISORY POSITION... WHILE AN AMSU-B PASS FROM 0624 UTC DEPICTED A POSSIBLE LOW-LEVEL CENTER MUCH FARTHER TO THE WEST-SOUTHWEST. CONVENTIONAL INFRARED SATELLITE IMAGERY SHOWS A WELL-DEFINED MID-LEVEL CIRCULATION EVEN FARTHER TO THE SOUTHWEST. AS STATED IN THE PREVIOUS DISCUSSION... THE LOW-LEVEL CENTER COULD BE REFORMING IN THIS AREA...HOWEVER...I AM HESITATE TO MAKE SUCH A SIGNIFICANT CHANGE WITHOUT VISIBLE IMAGERY OR OTHER MORE CONCLUSIVE EVIDENCE. DVORAK SATELLITE INTENSITY ESTIMATES ARE 45 KT FROM TAFB AND 35 KT FROM SAB. THE INITIAL INTENSITY WILL REMAIN AT 35 KT DUE TO THE UNCERTAINTY IN THE CURRENT POSITION AS WELL AS A DECREASE IN CONVECTIVE ACTIVITY OVER THE LAST SEVERAL HOURS. THE INTENSITY FORECAST IS HIGHLY DEPENDENT UPON A REFORMATION OF THE CENTER. IF THE CYCLONE CONTINUES TO STRUGGLE IN ORGANIZATION...THEN LITTLE STRENGTHENING WILL OCCUR. ON THE OTHER HAND IF REFORMATION OCCURS...A SLIGHTLY LESS SHEARED ENVIRONMENT AND 26-27C WATERS WOULD HELP THE CYCLONE INTENSIFY BEFORE ENCOUNTERING COOLER WATERS IN 3 OR SO DAYS. THE OFFICIAL INTENSITY FORECAST FOLLOWS CLOSELY WITH THE SHIPS...SUPERENSEMBLE...AND PREVIOUS FORECAST. THE INITIAL MOTION IS ESTIMATED AT 275/12. ERICK IS FORECAST TO CONTINUE TO BE STEERED TOWARD THE WEST OR WEST-NORTHWEST IN RESPONSE TO A MID-LEVEL RIDGE TO THE NORTH. AS WITH THE EARLIER MODEL GUIDANCE...THE GREATEST VARIATION IS WITH THE FORWARD MOTION. THE OFFICIAL TRACK IS A CONSENSUS OF THE GFDL...HWRF...GFS...AND UKMET SOLUTIONS. FORECAST POSITIONS AND MAX WINDS INITIAL 02/0900Z 13.3N 130.0W 35 KT 12HR VT 02/1800Z 13.4N 131.5W 35 KT 24HR VT 03/0600Z 13.5N 133.5W 40 KT 36HR VT 03/1800Z 13.8N 135.2W 45 KT 48HR VT 04/0600Z 14.2N 137.1W 45 KT 72HR VT 05/0600Z 14.5N 141.0W 45 KT 96HR VT 06/0600Z 14.5N 145.0W 40 KT 120HR VT 07/0600Z 14.5N 149.0W 40 KT $$ FORECASTER MAINELLI