WTPA43 PHFO 250241

TCDCP3



TROPICAL STORM DARBY DISCUSSION NUMBER  54

NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI   EP052016

500 PM HST SUN JUL 24 2016



Earlier thunderstorms southeast of Darby's centered dissipated

but vigorous thunderstorms just northeast of the center flared up

this afternoon with tops colder than -65C. The morning Hurricane

Hunter mission into Darby continued through mid-day with a maximum

surface wind of 37 kt found over the water east of the center.

Based on the aircraft recon data and the recent burst in deep

convection very close to Oahu and Kauai, Darby has been held at 35

kt for this advisory package. This could be generous, especially

considering that subjective Dvorak estimates all came in at 30 kt

and that no surface stations on Kauai and Oahu have reported

tropical storm force conditions thus far. Note that this was the

final mission into Darby. A big mahalo to the 53rd Weather

Reconnaissance Squadron for their outstanding support over the past

several days.



Darby is moving at 325/10 kt to the southwest of a lower and

middle-level pressure ridge. The main dynamical objective aids

remain tightly clustered and continue to indicate that Darby will

move northwestward over or near Kauai tonight, and continue toward

the northwest over the next 2 to 3 days while weakening to a

post-tropical remnant low. The forecast track for this package

remains close to the previous track and the dynamical consensus.



Current marginal sea surface temperatures will cool along the

forecast track and vertical shear, while forecast to be less

persistent than the previous cycle, should remain relatively strong

over the next day or so. As a result, the current forecast calls for

Darby to weaken to a tropical depression overnight, then become a

post-tropical remnant low in 48 hours. This is a faster weakening

than indicated by the intensity consensus.





FORECAST POSITIONS AND MAX WINDS



INIT  25/0300Z 21.7N 158.9W   35 KT  40 MPH

 12H  25/1200Z 22.7N 160.0W   30 KT  35 MPH

 24H  26/0000Z 23.8N 161.5W   30 KT  35 MPH

 36H  26/1200Z 25.0N 163.2W   30 KT  35 MPH

 48H  27/0000Z 26.4N 164.7W   30 KT  35 MPH...POST-TROP/REMNT LOW

 72H  28/0000Z 29.9N 166.8W   25 KT  30 MPH...DISSIPATED



$$

Forecaster Kodama