WTPA42 PHFO 270902 RRA

TCDCP2



TROPICAL STORM ULIKA DISCUSSION NUMBER   4

NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI   EP192016

1100 PM HST MON SEP 26 2016



SATELLITE IMAGERY INDICATES THAT THE TROPICAL CYCLONE HAS BECOME

BETTER ORGANIZED THIS EVENING, WITH DEEP CONVECTION NOW IN PLACE

OVER THE LOW LEVEL CIRCULATION CENTER. THE LATEST DVORAK INTENSITY

ESTIMATES FROM PHFO, SAB, AND JTWC RANGE FROM 2.0/30KT TO 2.5/35KT,

WITH THE ADT FROM UW-CIMSS SHOWING 2.9/43KT. BASED ON A

COMBINATION OF THE SATELLITE CLASSIFICATIONS, STEADY IMPROVEMENT IN

SATELLITE APPEARANCE SINCE A 26/1845Z ASCAT PASS SHOWING 30 KT

WINDS, THE SYSTEM HAS BEEN UPGRADED TO TROPICAL STORM ULIKA

(OO-LEE-KAH), WITH AN INITIAL INTENSITY OF 35 KT. ULIKA IS THE FIRST

SYSTEM TO DEVELOP IN THE CENTRAL PACIFIC DURING THE REGULAR 2016

TROPICAL CYCLONE SEASON.



THE INITIAL MOTION OF THE SYSTEM IS BASED ON SATELLITE ANIMATIONS,

AND IS SET AT 350 AT 3 KT. THE SYSTEM IS EXPECTED TO TRACK SLOWLY

NORTHWARD TONIGHT, THEN MAKE A TURN TOWARD THE NORTHEAST INTO A

WEAKNESS IN THE MID AND UPPER-LEVEL RIDGE RESULTING FROM AN UPPER

LEVEL LOW TO THE NORTH OF THE CYCLONE ON TUESDAY. THIS MOTION SHOULD

CONTINUE FOR THE NEXT COUPLE OF DAYS UNTIL INCREASING WESTERLY

VERTICAL WIND SHEAR RESULTS IN A MORE SHALLOW SYSTEM STEERED BY THE

LOW LEVEL TRADE WINDS TOWARD THE WEST WEDNESDAY NIGHT AND THURSDAY.

THE SYSTEM IS EXPECTED TO CONTINUE ON A WESTWARD TRACK WITH A

GRADUAL INCREASE IN FORWARD SPEED THROUGH THE END OF THE WEEK, AND

WEAKEN INTO A REMNANT LOW THURSDAY NIGHT OR FRIDAY. THE OFFICIAL

FORECAST TRACK IS VERY CLOSE TO THAT OF THE PREVIOUS ADVISORY,

AND IS ON THE WESTERN SIDE OF THE MULTI-MODEL CONSENSUS GUIDANCE.=