WTPA42 PHFO 231458

TCDCP2



TROPICAL STORM LOKE DISCUSSION NUMBER  11

NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI   CP042015

500 AM HST SUN AUG 23 2015



DEEP CONVECTION PERSISTED OVER THE APPARENT LOW-LEVEL CIRCULATION

CENTER /LLCC/ OF LOKE DURING MUCH OF THE NIGHT. THESE CLOUD TOPS

HAVE RECENTLY WARMED...BUT NEW DEEP CONVECTION IS INCREASING MAINLY

TO THE NORTH OF THE LLCC. DVORAK SUBJECTIVE T-NUMBERS CAME IN AT

T2.5/35KT FROM HFO/SAB...AND T.20/30KT FROM JTWC. LOKE IS MAINTAINED

AS A 35 KT TROPICAL STORM FOR THIS ADVISORY.



THE INITIAL MOTION OF LOKE IS ESTIMATED AT 350/08 KT...AIDED BY

A SERIES OF MICROWAVE IMAGES DURING THE LAST SEVERAL HOURS.

LOKE IS CURRENTLY MOVING NORTHWARD BETWEEN A MID-LEVEL RIDGE TO THE

EAST AND A WEAK MID- AND UPPER-LEVEL TROUGH TO THE WEST. THE CYCLONE

WILL ROUND THE WESTERN END OF THE MID-LEVEL RIDGE DURING THE NEXT

12 HOURS WHILE MOVING NORTHWARD JUST TO THE EAST OF THE

INTERNATIONAL DATE LINE. LOKE IS THEN FORECAST TO TURN TO THE

NORTHEAST WITH AN INCREASE IN FORWARD SPEED TONIGHT AND MONDAY...

AS IT COMES UNDER THE INFLUENCE OF A LARGE MID-LATITUDE CUTOFF LOW

DEVELOPING ALONG THE DATE LINE. THE GUIDANCE SUITE SHIFTED TO THE

RIGHT OR EAST ONCE AGAIN AT TAU 48 AND TAU 72...SWINGING LOKE

BACK TO THE NORTH THEN NORTHWEST AT TAU 72 AND BEYOND...AS THE

CYCLONE ROTATES AROUND THE WELL-DEFINED CUTOFF LOW LOCATED NORTHWEST

OF MIDWAY AT THAT TIME. THE NEW FORECAST TRACK IS VERY CLOSE TO THE

PREVIOUS TRACK AND IN THE MIDDLE OF TIGHTLY CLUSTERED GUIDANCE

THROUGH 36 HOURS...THEN IS SHIFTED AGAIN TO THE RIGHT OF THE

PREVIOUS TRACK AT 48 AND 72 HOURS AND IS NOW CLOSE TO THE

ECMWF...ALTHOUGH STILL NOT QUITE AS FAR TO THE RIGHT AS THE TCVN

CONSENSUS AND GFS TRACKS.



LOKE IS FORECAST TO MOVE ACROSS WARM SEA SURFACE TEMPERATURES

WITH AMPLE OCEAN HEAT CONTENT DURING THE NEXT COUPLE OF DAYS.

THE 1200 UTC UW-CIMSS ANALYSIS INDICATES VERY LOW VERTICAL

WIND SHEAR OF LESS THAN 5 KT...AND LITTLE SHEAR IS EXPECTED

ALONG THE FORECAST TRACK THROUGH AT LEAST 48 HOURS. WATER VAPOR AND

MIMIC-TPW SATELLITE IMAGERY SHOW DRIER AIR WRAPPING INTO LOKE/S

CIRCULATION FROM THE WEST SIDE...WHICH MAY CONTINUE TO INHIBIT

INTENSIFICATION SOMEWHAT DESPITE THE OTHERWISE FAVORABLE

CONDITIONS. THE NEW INTENSITY FORECAST GENERALLY FOLLOWS THE

IVCN CONSENSUS WITH SLOW INTENSIFICATION...AND BRINGS LOKE TO A

PEAK OF 55 KT BY TAU 48. LOKE IS FORECAST TO MAKE EXTRATROPICAL

TRANSITION BY TAU 96...THEN WILL BECOME ABSORBED WITHIN THE MUCH

LARGER EXTRATROPICAL CIRCULATION ASSOCIATED WITH FORMER SUPER

TYPHOON ATSANI.



TROPICAL STORM WATCHES HAVE BEEN ISSUED FOR THE WESTERN PORTION

OF THE PAPAHANAUMOKUAKEA MARINE NATIONAL MONUMENT...INCLUDING

MIDWAY. IF CURRENT FORECAST TRENDS CONTINUE...WARNINGS WILL

LIKELY NEED TO BE ISSUED LATER TODAY OR TONIGHT.





FORECAST POSITIONS AND MAX WINDS



INIT  23/1500Z 20.3N 179.5W   35 KT  40 MPH

 12H  24/0000Z 21.6N 179.3W   40 KT  45 MPH

 24H  24/1200Z 23.3N 178.3W   45 KT  50 MPH

 36H  25/0000Z 25.2N 176.8W   50 KT  60 MPH

 48H  25/1200Z 27.4N 175.3W   55 KT  65 MPH

 72H  26/1200Z 32.5N 176.0W   55 KT  65 MPH

 96H  27/1200Z 39.0N 177.5E   50 KT  60 MPH...POST-TROP/EXTRATROP

120H  28/1200Z...ABSORBED BY LARGER EXTRATROPICAL LOW



$$

FORECASTER JACOBSON/HOUSTON