000 WTPZ43 KNHC 140834 TCDEP3 TROPICAL STORM HECTOR DISCUSSION NUMBER 12 NWS NATIONAL HURRICANE CENTER MIAMI FL EP082012 200 AM PDT TUE AUG 14 2012 ALTHOUGH THE LOW-LEVEL CENTER HAS BECOME OBSCURED BY CIRRUS CLOUDS...RECENT MICROWAVE IMAGES INDICATE THAT IT IS STILL DISPLACED FROM THE DEEP CONVECTION. THE STRUCTURE OF THE STORM HAS CHANGED LITTLE OVER THE PAST FEW HOURS...SO THE INTENSITY IS BEING HELD AT 40 KT ON THIS ADVISORY. HECTOR HAS ANOTHER 48 HOURS OR SO OVER WATERS WARMER THAN 26.5C...BUT THE STORM WILL BE SUSCEPTIBLE TO DRIER AIR TO ITS NORTHWEST SINCE THE VERTICAL SHEAR IS NOT FORECAST TO ABATE. GRADUAL WEAKENING IS THEREFORE EXPECTED OVER THE NEXT COUPLE OF DAYS...AND HECTOR COULD BECOME A REMNANT LOW BY DAY 3. SOME OF THE INTENSITY MODELS HINT THAT IT COULD OCCUR EVEN SOONER THAN THAT. MICROWAVE FIXES SUGGEST THAT HECTOR HAS BEEN MOVING JUST SOUTH OF DUE WEST...AND THE MOTION ESTIMATE IS 265/5 KT. AS A LARGE MID- TO UPPER-LEVEL LOW OFF THE CALIFORNIA COAST AMPLIFIES OVER THE NEXT COUPLE OF DAYS...THE SUBTROPICAL RIDGE SHOULD BREAK DOWN AND ALLOW HECTOR TO TURN WEST-NORTHWESTWARD LATER TODAY. THIS MOTION SHOULD CONTINUE UNTIL HECTOR DEGENERATES INTO A REMNANT LOW...AT WHICH POINT IT WILL BE STEERED BY THE LOW-LEVEL FLOW AND TURN BACK TO THE WEST BY DAY 5. THE TRACK GUIDANCE IS IN BETTER AGREEMENT THAN IT HAD BEEN...AND THE NEW NHC TRACK FORECAST IS A LITTLE FASTER THAN THE PREVIOUS ONE ON DAYS 4 AND 5 TO BE CLOSER TO THE GFS...ECMWF... AND HFIP CONSENSUS TV15. FORECAST POSITIONS AND MAX WINDS INIT 14/0900Z 17.9N 114.0W 40 KT 45 MPH 12H 14/1800Z 18.1N 114.5W 40 KT 45 MPH 24H 15/0600Z 18.4N 115.3W 35 KT 40 MPH 36H 15/1800Z 18.8N 116.0W 35 KT 40 MPH 48H 16/0600Z 19.1N 116.6W 30 KT 35 MPH 72H 17/0600Z 20.0N 118.0W 25 KT 30 MPH...POST-TROP/REMNT LOW 96H 18/0600Z 21.0N 119.5W 20 KT 25 MPH...POST-TROP/REMNT LOW 120H 19/0600Z 21.0N 121.5W 15 KT 15 MPH...POST-TROP/REMNT LOW $$ FORECASTER BERG