Heavy Snow in Oregon, December 7 to 8, 2004

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OREGON
817 PM PST TUE DEC 7 2004

.DISCUSSION...NEGATIVE TILT UPPER TROUGH EXTENDS SOUTHEAST TO THE
PACNW COAST FROM AN UPPER LOW NEAR 50N/135W. ALSO A STRONG UPPER
LEVEL JET IS DRIVING A SERIES OF WAVES TOWARDS OREGON. THUS SHOULD
SEE DECENT CHANCES FOR PRECIP OVER THE REGION THROUGH WEDNESDAY. A
DEEP SURFACE LOW REMAINS OVER THE EASTERN PACIFIC AND LOOKS TO
SLOWLY LIFT NORTHEAST OVER THE NEXT 24 HOURS. THIS WILL KEEP THE
REGION UNDER A PERSISTENT SOUTHEAST TO SOUTH FLOW AT AND NEAR THE
SURFACE. BREEZY TO WINDY CONDITIONS WILL BE WIDESPREAD TONIGHT AND
WEDNESDAY. GRADIENTS SHOULD TIGHTEN ENOUGH TO SUPPORT WIND ADVISORY
LEVEL WINDS OVER THE GRANDE RONDE VALLEY TONIGHT/WEDNESDAY AND
ACROSS THE BLUE MOUNTAIN FOOTHILL AND LOWER COLUMBIA BASIN ZONES
WEDNESDAY. BRIEF HIGH GUSTS THIS EVENING ALONG THE OREGON BLUE
MOUNTAIN FOOTHILLS WERE PRODUCED BY A PASSING LINE OF SHOWERS. THESE
SOUTHEAST TO SOUTH LOW LEVEL WINDS SHOULD ALSO RESULT IN SUFFICIENT
UPSLOPE ENHANCEMENT OF THE PRECIPITATION ALONG THE EAST SLOPES OF
THE CASCADES AND INTO THE SOUTH SLOPES OF THE CENTRAL AND NORTHEAST
OREGON MOUNTAINS. THUS WILL CONTINUE THE CURRENT SNOW/BLOWING SNOW
ADVISORIES AND WARNINGS. DID ADJUST SNOW LEVEL WORDING IN THESE
ZONES TONIGHT AS SNOW LEVELS ARE GENERALLY AROUND 4000 FEET AT THE
MOMENT...EXPECT ALONG THE EAST SLOPES OF THE WASHINGTON CASCADES
WHERE SNOW LEVELS ARE AROUND 2000 FEET. STILL EXPECT THE SNOW LEVELS
TO RISE OVERNIGHT WITH THE BEST SNOW ACCUMULATIONS STILL TO OCCUR
ABOVE 4500 FEET THROUGH THE NEXT 24 HOURS. GKH

&&

.PRELIMINARY POINT TEMPS/POPS...
PENDLETON (AIRPORT) 044 053 042 049 / 060 070 050 050
WALLA WALLA         044 054 042 050 / 060 070 040 050
TRI-CITIES          041 056 039 049 / 060 060 030 040
YAKIMA              034 051 034 048 / 060 070 030 040
HERMISTON           041 055 039 050 / 060 060 040 040
ELLENSBURG          034 044 032 044 / 070 070 040 050
REDMOND             037 052 035 053 / 070 080 060 060
LA GRANDE           038 045 036 044 / 060 070 060 050
JOHN DAY            035 048 033 050 / 070 070 060 060
THE DALLES          039 052 037 050 / 060 060 040 050
&&

.PDT WATCHES/WARNINGS/ADVISORIES...
OR...WIND ADVISORY ORZ 044-045 WEDNESDAY AND 049 TONIGHT AND
WEDNESDAY MORNING. WINTER STORM WARNING ORZ 043 TONIGHT AND
WEDNESDAY. SNOW AND BLOWING SNOW ADVISORY TONIGHT AND WEDNESDAY
ORZ 042-048-050.
WA...WIND ADVISORY WAZ 028-029 WEDNESDAY. SNOW AND BLOWING SNOW
ADVISORY TONIGHT AND WEDNESDAY WAZ 025.
&&

FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON

HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE PENDLETON OREGON
306 PM PST TUE DEC 7 2004

ORZ041>050-WAZ024>030-081300-
NORTH CENTRAL OREGON-CENTRAL OREGON-LOWER COLUMBIA BASIN (OR)-
FOOTHILLS OF THE BLUE MOUNTAINS (OR)-BLUE MOUNTAINS-JOHN DAY BASIN-
OCHOCO-JOHN DAY HIGHLANDS-GRANDE RONDE VALLEY-WALLOWA COUNTY-
EASTERN COLUMBIA RIVER GORGE (WA)-
EAST SLOPES OF THE SOUTHERN CASCADES-KITTITAS VALLEY-YAKIMA VALLEY-
LOWER COLUMBIA BASIN (WA)-FOOTHILLS OF THE BLUE MOUNTAINS (WA)-
NORTHWEST BLUE MOUNTAINS-
306 PM PST TUE DEC 7 2004

THIS HAZARDOUS WEATHER OUTLOOK IS FOR CENTRAL AND NORTHEAST OREGON
AS WELL AS SOUTH CENTRAL AND SOUTHEAST WASHINGTON.

.DAY ONE...

HEAVY SNOW TONIGHT
     NORTH CENTRAL OREGON, CENTRAL OREGON, OCHOCO-JOHN DAY HIGHLANDS,
     WALLOWA COUNTY

STRONG WIND TONIGHT
     GRANDE RONDE VALLEY

.DAYS TWO THROUGH SEVEN...

HEAVY SNOW WEDNESDAY
          EAST SLOPES OF THE SOUTHERN CASCADES, NORTHWEST BLUE
          MOUNTAINS, NORTH CENTRAL OREGON, CENTRAL OREGON, BLUE
          MOUNTAINS, OCHOCO-JOHN DAY HIGHLANDS, WALLOWA COUNTY

STRONG WIND WEDNESDAY
          EASTERN COLUMBIA RIVER GORGE (WA), KITTITAS VALLEY, YAKIMA
          VALLEY, LOWER COLUMBIA BASIN (WA), FOOTHILLS OF THE BLUE
          MOUNTAINS (WA), EASTERN COLUMBIA RIVER GORGE (OR), LOWER
          COLUMBIA BASIN (OR), FOOTHILLS OF THE BLUE MOUNTAINS (OR),
          JOHN DAY BASIN, GRANDE RONDE VALLEY

A STRONG PACIFIC STORM SYSTEM WILL IMPACT THE AREA TONIGHT AND WEDNESDAY
BRINGING STRONG WINDS AND HEAVY MOUNTAIN SNOWS ABOVE 4500 FEET. NUMEROUS
ADVISORIES AND WARNINGS ARE IN EFFECT. REFER TO LATEST PDXWSWPDT AND PDXNPWPDT
FOR ADDITIONAL INFORMATION.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS LIKELY THROUGH WEDNESDAY EVENING AREAWIDE.

WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER
CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES.

PROTOTYPE GRAPHICAL FORECASTS OF WEATHER HAZARDS OUT TO SEVEN DAYS
ARE DISPLAYED ON THE WORLD WIDE WEB AT:

WWW.WRH.NOAA.GOV/PENDLETON/FORECAST/HWOGRAPHICS/HWOGRAPHICS.PHP

ALL LETTERS IN THE ABOVE URL ARE LOWER CASE...EXCEPT THE G IN
HWOGRAPHICS AND THE G IN HWOGRAPHICS.PHP.