000
WTPZ44 KNHC 300233
TCDEP4

Tropical Storm Hilary Discussion Number  35
NWS National Hurricane Center Miami FL       EP092017
800 PM PDT Sat Jul 29 2017

Satellite data indicate that Hilary is gradually losing
organization.  GOES-16 1-minute visible data show the center on the
northwestern side of a warming central dense overcast.  A
late-arriving ASCAT-A pass from 1808Z suggested maximum winds of
up to 55 kt.  With the degradation in the satellite presentation
since that time, the initial wind speed is set to 50 kt.  While
Hilary has been holding its own recently, the cold waters and dry
stable air mass of the eastern Pacific always end up winning, and a
steady weakening of Hilary should begin soon. The intensity forecast
is close to a blend of the previous interpolated forecast and the
HFIP-corrected intensity consensus.  Transition to a remnant low is
expected in about 24 hours due to Hilary moving over progressively
colder waters.

Hilary is moving a little faster and to the left, now 305/12.  The
storm should turn west-northwestward as it weakens and begins to
interact with the circulation of Irwin.  There is a reasonable
consensus in the models that one or both of the tropical cyclones
will dissipate before any merger can occur, and none of the major
models keep Hilary intact through 72 hours.  Thus the only change
is to show Hilary dissipated at that time, with only cosmetic
modifications made to the rest of the forecast.


FORECAST POSITIONS AND MAX WINDS

INIT  30/0300Z 22.9N 123.7W   50 KT  60 MPH
 12H  30/1200Z 23.9N 125.5W   40 KT  45 MPH
 24H  31/0000Z 25.0N 128.1W   30 KT  35 MPH...POST-TROP/REMNT LOW
 36H  31/1200Z 25.8N 130.5W   25 KT  30 MPH...POST-TROP/REMNT LOW
 48H  01/0000Z 26.0N 132.0W   20 KT  25 MPH...POST-TROP/REMNT LOW
 72H  02/0000Z...DISSIPATED

$$
Forecaster Blake