WTPA44 PHFO 181445
TCDCP4

TROPICAL STORM GUILLERMO DISCUSSION NUMBER  26
NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI   EP102009
500 AM HST TUE AUG 18 2009

GUILLERMO CONTINUES TO SHOW A WEAK CLOUD SIGNATURE ON SATELLITE
IMAGERY. THERE IS AN EXPOSED LOW LEVEL CIRCULATION CENTER WITH
CONVECTION SHEARED WELL TO THE NORTH. DESPITE THE WEAK APPEARANCE
ON SATELLITE DATA...A TIGHT PRESSURE GRADIENT BETWEEN GUILLERMO AND
A 1030 MB HIGH TO THE NORTH IS MAINTAINING TROPICAL STORM FORCE
WINDS. THIS TIGHT GRADIENT WILL CONTINUE...SO I AM FORECASTING 
GUILLERMO TO REMAIN AT ITS CURRENT STRENGTH FOR THE NEXT 12 HOURS 
AND TO REMAIN A TROPICAL STORM FOR 48 HOURS. THE WIND FIELD WILL 
REMAIN ASYMMETRIC...WITH TROPICAL STORM FORCE WINDS ONLY NORTH OF 
THE CENTER. GUILLERMO WILL THEN GRADUALLY WEAKEN AS IT TRACKS 
FARTHER WEST.
 
MOST OF THE TRACK GUIDANCE REMAINS CLOSELY GROUPED...ALTHOUGH THE
STATISTICAL MODELS ARE FAR TO THE RIGHT OF THE REST OF THE
GUIDANCE. I HAVE KEPT THE FORECAST TRACK NEAR THE CONSENSUS OF THE
DYNAMIC MODELS. GUILLERMO IS FORECAST TO CONTINUE MOVING NORTHWEST
FOR THE NEXT 24 HOURS...ALONG THE SOUTHWEST EDGE OF A SURFACE HIGH
FAR TO THE NORTH-NORTHEAST. AFTER 24 HOURS...GUILLERMO WILL CURVE
TO THE WEST...THEN SLIGHTLY SOUTH OF WEST...AS A NEW HIGH FAR
NORTH-NORTHWEST OF THE CYCLONE PUSHES SOUTH.
 
 
FORECAST POSITIONS AND MAX WINDS
 
INITIAL      18/1500Z 25.7N 149.9W    40 KT
 12HR VT     19/0000Z 27.3N 152.2W    40 KT
 24HR VT     19/1200Z 29.1N 155.7W    35 KT
 36HR VT     20/0000Z 30.0N 159.3W    35 KT
 48HR VT     20/1200Z 30.8N 162.6W    35 KT
 72HR VT     21/1200Z 31.0N 168.0W    30 KT
 96HR VT     22/1200Z 30.5N 173.5W    25 KT...DISSIPATING
120HR VT     23/1200Z 29.0N 179.0W    20 KT...REMNANT LOW
 
$$
FORECASTER DONALDSON