FXUS66 KPDT 291705
AFDPDT
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
905 AM PST SUN NOV 29 2009
.SHORT TERM...UPDATE...THE UPPER RIDGE CONTINUES TO BUILD OVER THE
REGION THIS MORNING WITH THE STORM TRACK LIFTING NORTH INTO BRITISH
COLUMBIA. SOME HIGH CLOUDINESS CONTINUES TO SPILL INTO THE REGION
THOUGH MUCH OF IT IS THIN. THE THICKEST CLOUD COVER REMAINS OVER
PORTIONS OF KITTITAS AND YAKIMA COUNTIES IN CENTRAL WASHINGTON...
WHERE CONDITIONS SHOULD STAY PARTLY TO MOSTLY CLOUD THROUGH THE DAY.
FOG AND LOW CLOUDINESS IS LIMITED THIS MORNING AND REMAINS NEAR
UKIAH...NEAR BOARDMAN AND ARLINGTON...AND IN PORTIONS OF THE JOHN
DAY RIVER VALLEY. EXPECT THESE SPOTS OF FOG AND LOW CLOUDINESS TO
PERSIST UNTIL NOON. WILL REMOVE MENTION OF FOG FROM MOST OTHER
AREAS. TEMPS AT MANY LOCATIONS ARE A DEGREE OR TWO AHEAD OF
YESTERDAY AND WILL NUDGE TEMPS UP 1 TO 3 DEGREES WHERE NEEDED. OTHER
UPDATES WILL BE TO REDUCE SOME CLOUD COVER OVER CENTRAL OREGON AND
TWEAK IT ELSEWHERE. 90
.LONG TERM...PREVIOUS DISCUSSION...THE UPPER LEVEL RIDGE WILL
REBUILD OVER THE PACIFIC NORTHWEST BY LATER TUESDAY AND WEDNESDAY...
WITH DRY STABLE CONDITIONS OVER EASTERN WASHINGTON AND OREGON.
PATCHY FOG MAY DEVELOP AGAIN IN THE LOWER COLUMBIA BASIN WEDNESDAY
NIGHT AS WARM AIR AT 850 MB ADVECTS INTO THE AREA AND STRENGTHENS
SURFACE BASED INVERSIONS. THURSDAY THROUGH SATURDAY THERE IS WIDE
SPREAD SOLUTIONS IN THE GFS ENSEMBLE AND TOTALLY DIFFERENT SOLUTIONS
BETWEEN THE ECMWF (RIDGE THURSDAY-FRIDAY AND TROUGH SATURDAY) AND
GFS (TROUGH THURSDAY AND NORTHERLY FLOW FRIDAY-SATURDAY). INCREASED
POPS THURSDAY-FRIDAY TO COVER UNCERTAINTY. EXPECT A DISTURBANCE TO
MOVE INTO THE REGION EITHER THURSDAY OR FRIDAY. THE DEPTH...SPEED
AND FORM THIS DISTURBANCE WILL TAKE HAS BEEN CHANGING WITH EACH
OPERATIONAL RUN OF THE VARIOUS MID-RANGE MODELS. MADE NO CHANGE TO
TEMPERATURES THURSDAY THROUGH SATURDAY THAT HINTED A COOLER NORTH
FLOW MAY SET UP BEHIND THIS DISTURBANCE.
&&
.AVIATION...PREVIOUS DISCUSSION...12Z TAFS...MAINLY VFR CONDITIONS
EXPECTED FOR THE NEXT 24 HOURS. POSSIBLE MVFR VISIBILITY IN PATCHY
FOG AT KYKM AND KPSC...AND IN AREAS SURROUNDING KPDT AND KALW THOUGH
NOT AT AIRPORT THROUGH 18Z...THEN EXPECT ALL TAF SITES TO BE FULL
VFR. WINDS UNDER 10 KTS.
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 46 32 44 31 / 0 0 0 10
ALW 48 35 44 34 / 0 0 0 10
PSC 48 29 44 28 / 0 0 0 10
YKM 44 28 45 27 / 0 0 0 10
HRI 48 28 44 27 / 0 0 0 10
ELN 50 30 44 29 / 0 0 0 10
RDM 47 25 47 24 / 0 0 0 0
LGD 43 30 43 29 / 0 0 0 10
GCD 44 31 47 30 / 0 0 0 10
DLS 49 32 46 31 / 0 0 0 10
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
&&
THREAT INDEX
TODAY : GREEN
MONDAY : GREEN
TUESDAY : GREEN
GREEN: NONE OR LIMITED NEED FOR WATCHES, WARNINGS, OR ADVISORIES.
YELLOW: A FEW WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
RED: NUMEROUS WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON
$$
90/83/83
