WTPA42 PHFO 241511

TCDCP2



TROPICAL STORM LOKE DISCUSSION NUMBER  15

NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI   CP042015

500 AM HST MON AUG 24 2015



LOKE HAS MAINTAINED A RATHER WELL DEFINED CENTRAL DENSE OVERCAST

DURING THE NIGHT...WITH A SERIES OF MICROWAVE IMAGES ALONG WITH A

0851 UTC ASCAT PASS CONFIRMING THAT THE LOW LEVEL CIRCULATION

CENTER IS REMAINING FIRMLY UNDERNEATH THE DEEP CONVECTION.

DVORAK SUBJECTIVE INTENSITY ESTIMATES CAME IN AT T3.5/55KT FROM

HFO...AND T3.0/45KT FROM SAB/JTWC. THE UW-CIMSS ADT INTENSITY

ESTIMATE REMAINS AT 67 KT...AND THE RECENT ASCAT PASS RETRIEVED

A SIGNIFICANT AREA OF 50-55 KT WINDS IN THE SOUTHEAST QUADRANT

OF LOKE. BASED ON A BLEND OF THE ABOVE DATA...THE INITIAL INTENSITY

IS INCREASED TO 55 KT FOR THIS ADVISORY.



THE INITIAL MOTION ESTIMATE IS 035/13. THERE IS NO SIGNIFICANT

CHANGE TO THE TRACK FORECAST PHILOSOPHY. THE PRIMARY FACTOR

CONTROLLING THE STEERING OF LOKE DURING THE NEXT 72 HOURS WILL BE A

LARGE MID-LATITUDE CUTOFF LOW WHICH IS FORECAST BY ALL OF THE GLOBAL

MODELS TO DROP SOUTHWARD TO THE WEST OF LOKE...THEN LINGER JUST TO

THE WEST OF MIDWAY. OBJECTIVE TRACK GUIDANCE IS IN REASONABLY GOOD

AGREEMENT...WITH LOKE ROTATING AROUND THE CUTOFF LOW DURING THIS

TIME. THIS WILL RESULT IN A CONTINUED NORTHEAST MOTION WITH LITTLE

CHANGE IN FORWARD SPEED TODAY AND TONIGHT...FOLLOWED BY A TURN TO

THE NORTH THEN NORTHWEST TUESDAY AND TUESDAY NIGHT. THE GUIDANCE

ENVELOPE ONCE AGAIN SHIFTED A BIT TO THE RIGHT FOR THIS CYCLE

THROUGH THE NEXT 36 HOURS...BUT THE ACTUAL BEST TRACK HAS BEEN

RUNNING TO THE LEFT OF MOST GUIDANCE DURING THE PAST 24 HOURS...

AND THE NEW OFFICIAL TRACK IS NUDGED ONLY SLIGHTLY TO THE RIGHT AND

REMAINS ON THE LEFT EDGE OF THE RELIABLE MODEL GUIDANCE THROUGH 48

HOURS. LOKE IS THEN FORECAST TO ACCELERATE RAPIDLY OFF TO THE

NORTHWEST BEYOND 48 HOURS...AS IT CONTINUES ROTATING AROUND THE

NORTH SIDE OF THE CUTOFF LOW NEAR MIDWAY AND BECOMES ENTRAINED IN

THE HUGE EXTRATROPICAL CIRCULATION ASSOCIATED WITH FORMER SUPER

TYPHOON ATSANI. LOKE IS FORECAST TO BECOME EXTRATROPICAL BY 72 HOURS

OVER THE NORTHWEST PACIFIC OCEAN...AND BY 96 HOURS SHOULD BE ABSORBED

INTO THE MUCH LARGER CIRCULATION OF EX-ATSANI.



LOKE WILL REMAIN OVER WARM SEA SURFACE TEMPERATURES OF 27-29C FOR

ANOTHER 24 HOURS...THEN WILL MOVE ACROSS COOLER WATERS NORTH OF 30N.

WHILE SOUTHWESTERLY VERTICAL WIND SHEAR IS INCREASING AS THE CYCLONE

MOVES FURTHER POLEWARD...THE MORE RAPID NORTHEAST MOTION

OF THE STORM SEEMS TO BE MAINTAINING SUFFICIENTLY LOW RELATIVE

SHEAR TO ALLOW FOR SOME FURTHER INTENSIFICATION DURING THE NEXT

24 TO 36 HOURS. THE NEW INTENSITY FORECAST IS SLIGHTLY BELOW THE

IVCN CONSENSUS AND SIMILAR TO THE PREVIOUS FORECAST...BRINGING LOKE

TO HURRICANE STRENGTH BY 24 HOURS. A STEADY WEAKENING TREND SHOULD

BEGIN AFTER 48 HOURS...AS THE CYCLONE MOVES ACROSS INCREASINGLY COOL

WATERS AND BEGINS EXTRATROPICAL TRANSITION.





FORECAST POSITIONS AND MAX WINDS



INIT  24/1500Z 25.2N 177.6W   55 KT  65 MPH

 12H  25/0000Z 26.7N 176.1W   60 KT  70 MPH

 24H  25/1200Z 29.1N 174.5W   65 KT  75 MPH

 36H  26/0000Z 31.9N 174.3W   70 KT  80 MPH

 48H  26/1200Z 35.0N 176.8W   65 KT  75 MPH

 72H  27/1200Z 44.0N 175.0E   50 KT  60 MPH...POST-TROP/EXTRATROP

 96H  28/1200Z...ABSORBED BY LARGER EXTRATROPICAL LOW



$$

FORECASTER JACOBSON/R BALLARD