Winter Storm in Oregon, January 15, 2005

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OREGON
230 AM PST SAT JAN 15 2005

CORRECTED HIGHLIGHT AREAS

.SHORT TERM...TODAY THROUGH SUNDAY...A PACIFIC STORM WILL SEND A
MOIST WARM FRONT ACROSS THE REGION TODAY...BRINGING SNOW TO THE
FORECAST AREA THIS MORNING. THERE IS A LAYER OF MODIFIED ARCTIC AIR
AT THE SURFACE WHICH WILL ENABLE ALL PRECIPITATION TO BEGIN AS SNOW
TODAY. WARM AIR ADVECTION WILL OVER-RIDE THE TOP OF THE MUCH COLDER
AIR AT THE SURFACE. THIS WARMER AIR ALOFT WILL EVENTUALLY RISE TO
ABOVE FREEZING THIS AFTERNOON OR TONIGHT FROM SOUTHWEST TO
NORTHEAST. ONCE IT BECOMES ABOVE FREEZING THE SNOW WILL MIX WITH AND
THEN CHANGE OVER TO SLEET OR FREEZING RAIN. AT THIS TIME QPF AMOUNTS
BY THE GUIDANCE INDICATES THAT IF IT WAS ALL SNOW THERE WOULD BE
ADVISORY AMOUNTS IN MOST AREAS. HOWEVER WITH THE COMBINATION OF THE
SNOW AND ICE EXPECTED THIS WARRANTS A WINTER STORM WARNING IN MANY
LOCATIONS. WILL LEAVE THE CURRENT WARNINGS GOING FOR CENTRAL OREGON
NORTH TO THE COLUMBIA RIVER GORGE AND EASTWARD ACROSS THE LOWER
COLUMBIA BASIN AND BLUE MOUNTAIN FOOTHILLS. AREAS EAST AND SOUTH OF
THIS WILL LIKELY NOT RECEIVE ENOUGH SNOW AND/OR ICE TO WARRANT
EITHER A SNOW ADVISORY OR A WINTER STORM WARNING. HOWEVER A WINTER
WEATHER ADVISORY MAY BE NEEDED FOR THOSE AREAS AND WILL CONSIDER
THAT FOR THE UPCOMING EARLY MORNING PACKAGE. FARTHER NORTHWEST ALONG
THE EAST SLOPES OF THE SOUTHERN WASHINGTON CASCADES THE PRECIP TYPE
WILL BE MOSTLY SNOW WITH JUST A BRIEF PERIOD OF LIGHT FREEZING RAIN
OR SLEET BEFORE ENDING. THEREFORE WILL CANCEL THE WINTER STORM WATCH
FOR THAT AREA AND GO WITH A SNOW ADVISORY. THE PRECIPITATION WILL
END SUNDAY AFTERNOON IN THE LOWER ELEVATIONS...WITH JUST ISOLATED
RAIN OR SNOW SHOWERS OVER THE MOUNTAINS INTO SUNDAY EVENING. RSC.

.LONG TERM...SUNDAY NIGHT THROUGH FRIDAY...UPPER RIDGE IS STILL
EXPECTED TO BUILD OVER THE PACIFIC NORTHWEST...THOUGH AMPLITUDE
LOOKS TO BE MODERATE. WAVES WILL MOVE OVER THE RIDGE AT TIMES
PRODUCING A CHANCE OF PRECIP...MAINLY OVER THE MOUNTAINS. A STRONGER
WAVE MAY MOVE AFFECT OUR NORTHERN ZONES MONDAY NIGHT AND
TUESDAY...THOUGH WEST FLOW WILL LIMIT PRECIP IN THE LOWER BASIN.
SURFACE LOW TEMPS WILL CONTINUE COOL AT NIGHT WHILE SNOW LEVELS WILL
BE HIGHER...THUS SOME LIGHT FREEZING PRECIP MAY BE POSSIBLE IN THE
VALLEYS OF THE CASCADE EAST SLOPES AND THE LOWER COLUMBIA BASIN OF
WASHINGTON MONDAY NIGHT. THE RIDGE MAY AMPLIFY MID TO LATE WEEK
KEEPING MOST PRECIP TO OUR NORTH...BUT UNCERTAINTY REMAINS HIGH FOR
LATE NEXT WEEK. GKH.

&&

.PRELIMINARY POINT TEMPS/POPS...
PENDLETON (AIRPORT) 029 019 037 / 080 080 050
WALLA WALLA         024 019 035 / 080 080 050
TRI-CITIES          022 018 032 / 080 080 050
YAKIMA              022 019 028 / 080 080 050
HERMISTON           024 018 037 / 080 080 050
ELLENSBURG          022 016 029 / 080 080 050
REDMOND             031 033 042 / 080 080 040
LA GRANDE           031 021 040 / 070 080 050
JOHN DAY            031 023 040 / 080 080 040
THE DALLES          026 021 036 / 080 080 050
&&

.PDT WATCHES/WARNINGS/ADVISORIES...
OR...WINTER STORM WARNING FOR OREGON ZONES 41..42..43 FROM 6AM TODAY
     THROUGH 6 AM SUNDAY.
  ...WINTER STORM WARNING FOR OREGON ZONES 44 AND 45 FROM NOON TODAY
     UNTIL NOON SUNDAY.
WA...WINTER STORM WARNING FOR WASHINGTON ZONE 24 FROM 6AM TODAY
     THROUGH 6AM SUNDAY.
  ...WINTER STORM WARNING FOR WASHINGTON ZONES 26..27..28 AND 29
     FROM NOON TODAY THROUGH NOON SUNDAY.
  ...SNOW ADVISORY FOR WASHINGTON ZONE 25 FROM NOON TODAY THROUGH
     NOON SUNDAY.
  ...WINTER WEATHER ADVISORY FOR OREGON ZONES 47 AND 49 FROM NOON
     TODAY THROUGH NOON SUNDAY.

&&

TI:YYG
FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON
88

HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE PENDLETON OREGON
300 PM PST FRI JAN 14 2005

ORZ041>050-WAZ024>030-151300-
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-
300 PM PST FRI JAN 14 2005

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

.DAY ONE...TODAY AND TONIGHT

EXTREME COLD
     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, EASTERN COLUMBIA RIVER GORGE (OR), 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

MODIFIED ARCTIC AIR WILL REMAIN OVER THE REGION THROUGH TONIGHT
RESULTING IN CONTINUED COLD TEMPERATURES.  A MOIST WARM FRONT WILL
APPROACH CENTRAL AND NORTH CENTRAL OREGON LATE TONIGHT...BRINGING
WITH IT A CHANCE OF SNOW.

.DAYS TWO THROUGH SEVEN...

WINTER MIX SATURDAY
          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, EASTERN COLUMBIA RIVER GORGE
          (OR), 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

SNOW SATURDAY
          WALLOWA COUNTY

A WARM FRONT IS EXPECTED TO MOVE THROUGH THE AREA ON SATURDAY AND
SATURDAY NIGHT...BRINGING A MIXED BAG OF WINTERY PRECIPITATION TO
THE REGION.  NUMEROUS WARNINGS AND WATCHES ARE IN EFFECT.  PLEASE
SEE PRODUCT PDXWSWPDT WWUS46 KPDT FOR FURTHER DETAILS.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION WILL BE LIKELY.

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.