159 
FLUS46 KPDT 011940 AAA
HWOPDT

HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE PENDLETON OR
1140 AM PST MON DEC 1 2008

UPDATED FOR ADVISORY CHANGES

ORZ041>044-049-050-501>506-WAZ024-026>030-501-502-021415-
EASTERN COLUMBIA RIVER GORGE OF OREGON-NORTH CENTRAL OREGON-
CENTRAL OREGON-LOWER COLUMBIA BASIN OF OREGON-GRANDE RONDE VALLEY-
WALLOWA COUNTY-FOOTHILLS OF THE BLUE MOUNTAINS OF OREGON-
NORTHERN BLUE MOUNTAINS OF OREGON-
SOUTHERN BLUE MOUNTAINS OF OREGON-
NORTHERN WHEELER AND SOUTHERN GILLIAM COUNTIES-JOHN DAY BASIN-
OCHOCO-JOHN DAY HIGHLANDS-
EASTERN COLUMBIA RIVER GORGE OF WASHINGTON-KITTITAS VALLEY-
YAKIMA VALLEY-LOWER COLUMBIA BASIN OF WASHINGTON-
FOOTHILLS OF THE BLUE MOUNTAINS OF WASHINGTON-
NORTHWEST BLUE MOUNTAINS-
EAST SLOPES OF THE CENTRAL CASCADES OF WASHINGTON-
EAST SLOPES OF THE SOUTHERN CASCADES OF WASHINGTON-
1140 AM PST MON DEC 1 2008

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

.DAY ONE...REST OF TODAY AND TONIGHT

AIR STAGNATION ADVISORY
      YAKIMA VALLEY

DRY AND VERY STABLE CONDITIONS HAVE WARRANTED AN AIR STAGNATION 
ADVISORY IN EFFECT UNTIL 3 PM PST TUESDAY FOR THE YAKIMA VALLEY. 
RELATIVELY LIGHT WINDS AND A LACK OF MIXING WILL RESULT IN 
POLLUTANTS BEING TRAPPED NEAR THE GROUND. DETAILS CAN BE FOUND IN 
THE PRODUCT PDXNPWPDT.

A PACIFIC LOW PRESSURE SYSTEM WILL MOVE EAST OF THE CASCADES 
TONIGHT...BRINGING WIDESPREAD RAIN.  INCREASING WINDS WILL ALSO 
RESULT IN BETTER MIXING FOR IMPROVED AIR QUALITY FOR THE REMAINING 
FORECAST AREA.  WINDS IN THE GRANDE RONDE VALLEY TODAY WILL 
GRADUALLY DECREASE THROUGH THE EVENING HOURS


.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY

AIR STAGNATION ADVISORY
      YAKIMA VALLEY

THE ADVISORY CONTINUES THROUGH 3 PM TUESDAY WHEN CONDITIONS ARE 
EXPECTED TO IMPROVE.

THE AFOREMENTIONED LOW PRESSURE SYSTEM WILL BRING SCATTERED TO 
NUMEROUS SHOWERS ON TUESDAY.  DRIER AND COOLER AIR WILL SPREAD 
ACROSS THE REGION TUESDAY NIGHT...AND ONLY ISOLATED MOUNTAIN RAIN 
AND SNOW SHOWERS ARE EXPECTED ON WEDNESDAY.  DRY CONDITIONS ARE 
EXPECTED THURSDAY AND FRIDAY BEFORE THE NEXT SYSTEM ARRIVES FRIDAY 
NIGHT AND SATURDAY.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT ANTICIPATED AT THIS TIME.

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

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

WWW.WRH.NOAA.GOV/PDT/CURRENTHAZARDS/HWO.HTML

ALL LETTERS IN THE ABOVE URL ARE LOWER CASE...EXCEPT THE H IN
CURRENTHAZARDS.

$$