000 WTPZ44 KNHC 261437 TCDEP4 HURRICANE FRANK DISCUSSION NUMBER 20 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL EP092010 800 AM PDT THU AUG 26 2010 A 0907 UTC TRMM OVERPASS SHOWED THE PRESENCE OF AN EYE ON BOTH THE 37 AND 85 GHZ CHANNELS...THOUGH THIS FEATURE IS NOT APPARENT IN CONVENTIONAL SATELLITE IMAGERY. DVORAK CLASSIFICATIONS HAVE INCREASED TO 90 KT AND 77 KT FROM TAFB AND SAB...RESPECTIVELY. OBJECTIVE SATELLITE ESTIMATES FROM UW-CIMSS ARE IN THE 70-75 KT RANGE. THE INITIAL INTENSITY IS SET AT 75 KT...NEAR THE LOWER END OF THE ESTIMATES...DUE TO THE ELONGATED CLOUD PATTERN. THE HURRICANE REGIONAL AND STATISTICAL MODELS SHOW ARRESTED DEVELOPMENT OR GRADUAL WEAKENING DURING THE NEXT DAY OR SO...LIKELY IN RESPONSE TO AN INCREASE IN EAST-NORTHEASTERLY SHEAR. FRANK IS EXPECTED TO CROSS THE 26 DEGREE C SST ISOTHERM IN 36-48 HOURS AND A MORE STEADY WEAKENING IS ANTICIPATED BEYOND THAT TIME. LITTLE CHANGE WAS MADE TO THE INTENSITY FORECAST...AND IT IS IN BEST AGREEMENT WITH THE LGEM INTENSITY MODEL. THE INITIAL MOTION ESTIMATE IS 275/10...A LITTLE SOUTH OF THE PREVIOUS TRACK. FRANK IS EXPECTED TO RESUME A WEST-NORTHWESTWARD MOTION DURING THE NEXT 12-24 HOURS AS IT IS STEERED BY A MID-LEVEL RIDGE CENTERED OVER THE SOUTHWESTERN UNITED STATES. THEREAFTER...A TURN TO THE NORTHWEST AND THEN NORTH WITH A DECREASE IN FORWARD SPEED IS FORECAST AS A DEEP LAYER TROUGH AMPLIFIES NEAR THE WEST COAST OF THE UNITED STATES. THE NHC OFFICIAL TRACK FORECAST IS NUDGED SLIGHTLY TO THE SOUTH OF THE PREVIOUS ONE FOR THE NEXT 36-48 HOURS...TO ACCOUNT FOR THE INITIAL POSITION AND MOTION...AND IS OTHERWISE SIMILAR. FORECAST POSITIONS AND MAX WINDS INITIAL 26/1500Z 17.4N 109.3W 75 KT 12HR VT 27/0000Z 17.8N 110.8W 75 KT 24HR VT 27/1200Z 18.2N 112.2W 70 KT 36HR VT 28/0000Z 18.9N 113.3W 65 KT 48HR VT 28/1200Z 19.6N 113.9W 55 KT 72HR VT 29/1200Z 21.0N 114.0W 45 KT 96HR VT 30/1200Z 22.0N 114.0W 30 KT 120HR VT 31/1200Z 23.0N 114.0W 25 KT...POST-TROP/REMNT LOW $$ FORECASTER CANGIALOSI