WTPA44 PHFO 071458
TCDCP4

POST-TROPICAL CYCLONE GUILLERMO DISCUSSION NUMBER  35
NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI   EP092015
500 AM HST FRI AUG 07 2015
 
A PARTIAL NARROW RING OF ISOLATED THUNDERSTORMS AND SCATTERED 
TOWERING CUMULUS CLOUDS HAS RECENTLY DEVELOPED IN THE SOUTHEASTERN 
SEMICIRCLE OF GUILLERMO. HOWEVER...THE REMAINDER OF THE CIRCULATION 
HAS NO DEEP CONVECTION...AND THE CENTER OF THE CIRCULATION APPEARS 
TO BE ALMOST COMPLETELY CLOUD FREE. SINCE THERE IS NO DEEP 
CONVECTION NEAR THE INNER CORE OF THIS SYSTEM...IT IS EVIDENT THAT 
GUILLERMO HAS CONTINUED TO LOSE TROPICAL CYCLONE CHARACTERISTICS 
TONIGHT. MORE IMPORTANTLY...AN ASCAT PASS OVER THE CORE OF GUILLERMO 
AROUND 0801Z SHOWED NO CLOSED CIRCULATION AT THE SURFACE. INSTEAD... 
THERE APPEARED TO BE A NORTH-NORTHEAST TO SOUTH-SOUTHWEST ORIENTED 
SURFACE TROUGH UNDERNEATH A RATHER WELL-DEFINED CLOUD LEVEL 
CIRCULATION. THE ASCAT DATA ALSO SHOWED A NEARLY 105 NM WIDE BAND OF 
25 TO 30 KT WINDS ALONG THE NORTH AND NORTHEAST PERIPHERY OF THIS 
TROUGH. WINDS ALONG AND ON EITHER SIDE OF THE TROUGH AXIS WERE 20 KT 
OR LESS. ALSO...NO SATELLITE FIX AGENCY WAS ABLE TO CLASSIFY 
GUILLERMO FOR THIS ADVISORY. AS A RESULT...GUILLERMO IS BEING 
DECLARED A POST-TROPICAL CYCLONE AS OF THIS ADVISORY PACKAGE.

THE CURRENT MOTION FOR THE REMNANTS OF GUILLERMO IS 285 DEGREES AT
15 KT. THE FINAL FORECAST TRACK SHOWS GUILLERMO WILL CONTINUE
THIS SAME GENERAL MOVEMENT FOLLOWING A RELATIVELY TIGHT CLUSTER OF
GUIDANCE INTO SATURDAY. THE TRUNCATED TRACK MOST CLOSELY RESEMBLES
THE LATEST ECMWF GUIDANCE. THE INITIAL INTENSITY OF 30 KT IS BASED
ON THE EARLIER ASCAT PASS. ASSUMING THE STRONG PRESSURE GRADIENT
BETWEEN THE REMNANTS OF GUILLERMO AND THE SUBTROPICAL RIDGE FAR
NORTH OF HAWAII REMAINS IN PLACE...WINDS OF 30 KT WILL LIKELY
CONTINUE TODAY. HOWEVER...AS THE SYSTEM CONTINUES TO MOVE RAPIDLY
TOWARD THE WEST-NORTHWEST AND WEAKENS...THE WINDS ARE EXPECTED TO
GRADUALLY DIMINISH TONIGHT...WITH DISSIPATION LIKELY OCCURRING BY
SATURDAY. THIS WILL BE THE FINAL ADVISORY ISSUED ON THIS 
SYSTEM...UNLESS RE-GENERATION OCCURS.
 
FOR ADDITIONAL INFORMATION ON THE REMNANT LOW...PLEASE SEE HIGH
SEAS FORECASTS ISSUED BY THE NATIONAL WEATHER SERVICE...UNDER AWIPS 
HEADER HFOHSFNP AND WMO HEADER FZPN40 PHFO. 
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  07/1500Z 22.7N 158.9W   30 KT  35 MPH
 12H  08/0000Z 23.3N 161.4W   30 KT  35 MPH...POST-TROP/REMNT LOW
 24H  08/1200Z 24.2N 164.7W   25 KT  30 MPH...POST-TROP/REMNT LOW
 36H  09/0000Z...DISSIPATED
 
$$
FORECASTER HOUSTON