500 AM HST TUE AUG 11 2015 HILDA CONTINUES TO WEAKEN IN THE FACE OF STRONG SOUTHWESTERLY SHEAR...ANALYZED AS BEING NEAR 35 KT BY UW-CIMSS. LATEST SUBJECTIVE DVORAK SATELLITE DATA-T VALUES FROM HFO/SAB/PGTW RANGE FROM 4.0/65 KT TO 4.5/77 KT...WHILE LATEST ADT VALUES ARE 4.4. BASED ON A BLEND OF THESE ESTIMATES...AND A STEADILY DEGRADING SATELLITE APPEARANCE...THE INITIAL INTENSITY FOR THIS ADVISORY HAS BEEN LOWERED TO 75 KT. THE INITIAL MOTION VECTOR FOR THIS ADVISORY IS A SOMEWHAT UNCERTAIN 315/06 KT...AS IT IS DIFFICULT TO DETERMINE EXACTLY WHERE THE CENTER IS USING INFRARED IMAGERY...AND THERE HAVE NOT BEEN ANY USABLE MICROWAVE PASSES OVER THE PAST 6 HOURS OR SO. ALTHOUGH THE UPPER LEVEL FLOW OVER HILDA FEATURES RELATIVELY STRONG SOUTHWESTERLY WINDS...THE CYCLONE IS CURRENTLY IN AN AREA OF LIGHT STEERING WINDS BETWEEN A LOW ALOFT NORTH OF HAWAII...AND A HIGH TO THE DISTANT EAST. THIS WILL INDUCE HILDA TO MOVE SLOWLY TOWARD THE NORTHWEST THROUGH WEDNESDAY. THEREAFTER...HILDA IS EXPECTED TO MOVE A LITTLE MORE QUICKLY TOWARD THE WEST...AS THE SHALLOW SYSTEM IS STEERED BY THE LOW-LEVEL TRADE FLOW. THE OFFICIAL TRACK FORECAST IS ESSENTIALLY AN UPDATE OF THE PREVIOUS...AND NOW LIES ON THE RIGHT HAND SIDE OF A GUIDANCE ENVELOPE THAT HAS BEEN ANYTHING BUT CONSISTENT BETWEEN MODEL RUNS. HILDA IS LIVING ON BORROWED TIME...AND WILL SOON GIVE IN TO THE HOSTILE ENVIRONMENT IN WHICH IT IS EMBEDDED. STRONG WESTERLY WINDS ALOFT...ASSOCIATED WITH THE SUBTROPICAL JET...LIE ALONG THE FORECAST PATH. THUS HILDA IS FORECAST TO STEADILY WEAKEN THROUGH THE FORECAST PERIOD...WITH DISSIPATION FORECAST BY DAY 5. IN THE MEANTIME HOWEVER...HILDA WILL APPROACH THE BIG ISLAND FROM THE SOUTHEAST...AND UNCERTAINTIES ASSOCIATED WITH THE RATE OF WEAKENING HAVE LED TO THE ISSUANCE OF A TROPICAL STORM WATCH FOR THE BIG ISLAND WITH THIS PACKAGE. THE UPDATED INTENSITY FORECAST ALSO CLOSELY FOLLOWS THE PREVIOUS...AND IS CLOSE TO SHIPS GUIDANCE THROUGH 48 HOURS. THE RATE OF FORECAST WEAKENING THEREAFTER IS CLOSE TO THE IVCN CONSENSUS...BUT SLOWER THAN SHIPS GUIDANCE. WHILE UNCERTAINTY REMAINS AS TO THE EVENTUAL IMPACTS THAT MAY BE FELT IN THE HAWAIIAN ISLANDS FROM HILDA...THE POTENTIAL FOR VERY HEAVY RAINFALL APPEARS TO BE INCREASING. RECONNAISSANCE FLIGHTS INTO HILDA WILL OCCUR AT 6 HOURLY INTERVALS STARTING THIS EVENING...WITH THE NEXT MISSION SLATED FOR THIS MORNING. FORECAST POSITIONS AND MAX WINDS INIT 11/1500Z 17.5N 151.3W 75 KT 85 MPH 12H 12/0000Z 17.9N 151.9W 65 KT 75 MPH 24H 12/1200Z 18.4N 152.6W 55 KT 65 MPH 36H 13/0000Z 18.8N 153.3W 45 KT 50 MPH 48H 13/1200Z 19.1N 154.4W 35 KT 40 MPH 72H 14/1200Z 19.4N 156.8W 30 KT 35 MPH 96H 15/1200Z 19.5N 159.5W 25 KT 30 MPH...POST-TROP/REMNT LOW 120H 16/1200Z...DISSIPATED