000 WTPZ42 KNHC 211455 TCDEP2 HURRICANE FAUSTO DISCUSSION NUMBER 22 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL EP072008 800 AM PDT MON JUL 21 2008 HURRICANE FAUSTO'S MID TO UPPER LEVEL CENTER IS BECOMING DECOUPLED FROM THE SURFACE CIRCULATION. WHILE GEOSTATIONARY INFRARED SATELLITE PICTURES SUGGESTED A CONTINUED TRACK TOWARD THE NORTHWEST OVERNIGHT...MICROWAVE IMAGERY FROM AMSR AND AMSU INSTEAD SHOW THAT THE LOW-LEVEL CENTER IS SUBSTANTIALLY SOUTHWEST OF THE 06Z AND 12Z GEOSTATIONARY-BASED POSITION ESTIMATES. THIS DECOUPLING ALSO INDICATES THAT THE HURRICANE MAY NOT BE AS STRONG AS SUGGESTED BY THE DVORAK ESTIMATES FROM TAFB AND SAB. THE AFOREMENTIONED AMSU PASS AT 0936Z GAVE AN INTENSITY ESTIMATE FROM CIMSS OF 67 KT...WHICH IS SUBSTANTIALLY WEAKER THAN EARLIER AMSU ANALYSES. THE CURRENT INTENSITY IS ESTIMATED TO BE 70 KT...BUT THIS MAY BE SLIGHTLY ON THE HIGH SIDE. FAUSTO IS MOVING AT AN UNCERTAIN 300 DEGREES AT 12 KT. THE CYCLONE IS SITUATED SOUTHWEST OF A DEEP-LAYERED RIDGE OVER NORTHERN MEXICO AND SOUTHEAST OF A VIGOROUS CUTOFF LOW WEST OF CALIFORNIA. GIVEN THE DECOUPLING OF THE LOW AND MID-LEVEL CIRCULATIONS THAT APPEARS TO BE OCCURRING...FAUSTO SHOULD NO LONGER FEEL THE INFLUENCE OF THE MID AND UPPER LEVEL FEATURES AND INSTEAD BE INCREASINGLY ADVECTED ALONG BY THE LOWER LEVEL FLOW. THE FORECAST IS A CONSENSUS OF THE GFDL...UKMET...NOGAPS...AND ECMWF MODELS AND IS SLIGHTLY SOUTH OF THE PREVIOUS FORECAST. THE DECOUPLING MAY BE DUE TO THE COMBINATION OF INCREASINGLY HOSTILE THERMODYNAMICS AND MODERATE SOUTHERLY SHEAR IMPACTING THE CYCLONE. CONTINUED WEAKENING IS ANTICIPATED AS FAUSTO SHOULD MOVE OVER EVEN COLDER WATERS WITHIN THE NEXT 24 TO 36 HOURS. THE INTENSITY FORECAST IS A BLEND OF THE LGEM...SHIPS...HWRF...AND GFDL MODELS...BUT IS SUBSTANTIALLY LOWER THAN THE PREVIOUS ADVISORY. FORECAST POSITIONS AND MAX WINDS INITIAL 21/1500Z 20.4N 116.8W 70 KT 12HR VT 22/0000Z 21.1N 118.4W 55 KT 24HR VT 22/1200Z 21.8N 120.5W 45 KT 36HR VT 23/0000Z 22.2N 122.4W 35 KT 48HR VT 23/1200Z 22.6N 123.9W 30 KT 72HR VT 24/1200Z 23.5N 127.0W 20 KT...REMNANT LOW 96HR VT 25/1200Z...DISSIPATED $$ FORECASTER LANDSEA/KNABB