000 
FXUS66 KPQR 102132
AFDPQR

NORTHWEST OREGON AND SOUTHWEST WASHINGTON FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND OR
300 PM PDT WED SEP 10 2003

.SYNOPSIS...ANOTHER WEAK PACIFIC SYSTEM WILL MOVE INTO THE PACIFIC
NORTHWEST THIS EVENING FOR SOME AREAS OF LIGHT RAIN. ANOTHER
DISTURBANCE WILL FOLLOW THU BUT MAINLY AFFECT THE NORTHERN ZONES. AN
UPPER RIDGE WILL DEVELOP OVER THE EASTERN PACIFIC THU NIGHT AND
FRI...WHICH WILL PUSH WHAT REMAINS OF THE MOISTURE THROUGH THE
FORECAST AREA INTO EARLY FRI...BEFORE DRYING FRI AFTERNOON THAT WILL
CONTINUE THROUGH SUN.

.DISCUSSION...
.SHORT TERM...SATELLITE LOOPERS SHOW A WEAK FRONTAL BAND NEARING THE
COAST WHICH SHOULD GIVE AREAS OF LIGHT RAIN THIS EVENING AS IT MOVES
INLAND. AWIPS TIMER SHOWS THE BAND EAST OF THE DISTRICT BY LATE
EVENING...THEN A POSSIBLE BREAK OR DECREASE IN RAIN THREAT OVERNIGHT.

ANOTHER SURGE PUSHES ONSHORE THU BUT WITH A LITTLE HIGHER 500 MB
HEIGHTS WILL CONFINE CHANCE POPS TO THE NORTH. AN UPPER RIDGE
DEVELOPING IN THE EASTERN PAC THU NIGHT AND FRI WILL INITIALLY
PUSHES THE REMAINS OF THIS MOISTURE SOUTHEAST THROUGH THE FORECAST
AREA...FOLLOWED BY DRYING AND CLEARING FRI AFTERNOON PER THE 12Z GFS
AND MESO ETA.

GUIDANCE STILL SHOWS THE EASTERN PAC UPPER RIDGE SHARPENING AND
MOVING OVER THE DISTRICT FRI NIGHT INTO SAT NIGHT FOR SUNNY
CONDITIONS WITH NORTHEAST OFFSHORE WINDS POSSIBLE FAVORED AREAS. WITH
THE MOIST GROUND COULD ALSO BE PATCHY MORNING FOG SHELTERED AREAS.
WITH PREDOMINATE NORTHERLY FLOW OVER THE AREA ONLY SOUTHERN ZONES
APPEAR TO HAVE THE POTENTIAL TO REACH INTO THE LOWER 80S.

.LONG TERM...GFS THE FASTEST IN BREAKING DOWN THE RIDGE WITH 500 MB
HEIGHTS ALREADY FALLING ON SUN AS A SHORT WAVE DIGS INTO WA. SHOULD
REMAIN DRY SUN...THEN A THREAT OF RAIN FOR THE REMAINDER OF THE
EXTENDED ESPECIALLY NORTH AS THE MODELS SHOW LOWER HEIGHTS OVER THE
NORTHEAST PAC ALTHOUGH WITH NOTICEABLY DIFFERENT DETAILS. WILLIS

AST 56342  PDX 35342  SLE 23232  EUG 22122

.PQR...SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR.

$$