Heavy Snow in Oregon, December 27 to 28, 2003

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OREGON
900 AM PST SAT DEC 27 2003

.DISCUSSION...A SYSTEM IS CURRENTLY MOVING THROUGH THE AREA THIS
MORNING...BRINGING MOSTLY SNOW SHOWERS TO THE REGION.  HOWEVER...MAY
LOCATIONS IN THE BASIN AND FOOTHILLS ARE JUST AROUND THE FREEZING
MARK...AND ALTHOUGH THE SNOW SEEMS TO BE STICKING...IT IS NOT
ACCUMULATING.  SNOW LEVELS WILL ALSO BE RISING TO AROUND 1500 FEET
TODAY...SO THE BASIN LOCATIONS MAY SEE A MIX OF RAIN AND
SNOW...BEFORE TURNING TO RAIN AS THIS SYSTEM EXITS THE AREA.

OTHERWISE...THIS IS THE FIRST SYSTEM OF TWO MOVING THROUGH THE
PACIFIC NORTHWEST TODAY.  THE NEXT SYSTEM IS NOW MOVING ONSHORE AS
SEEN ON SATELLITE AND RADAR IMAGERY...AND WILL BE CROSSING OVER
CASCADES LATER THIS AFTERNOON.  THIS SYSTEM HAS GOOD UPPER LEVEL
SUPPORT AND PLENTY OF MOISTURE AND COLD AIR ASSOCIATED WITH IT.  AS
A RESULT...SNOW LEVELS WILL BE DROPPING BACK DOWN TO THE SURFACE
TONIGHT...AND SNOW WILL CONTINUE ACROSS THE AREA.  A SNOW ADVISORY
HAS BEEN ISSUED FOR THE EAST SLOPES OF THE WASHINGTON CASCADES FOR
LATER THIS AFTERNOON THROUGH TONIGHT...AND A WINTER STORM WATCH HAS
BEEN ISSUED FOR THE BLUE AND WALLOWA MOUNTAINS FOR TONIGHT.  STILL
NEED TO EXAMINE THE SITUATION MORE CLOSELY...BUT WILL MOST LIKELY
UPGRADE THE WATCH TO AT LEAST A SNOW ADVISORY...AND POSSIBLE A
WARNING THIS AFTERNOON.  WILL ALSO NEED TO CLOSELY LOOK AT SNOW
AMOUNTS FOR THE FOOTHILLS OF THE BLUES AS WELL AS THE GRANDE RONDE
VALLEY AS THEY MAY BE PUSHING ADVISORY CRITERIA AS WELL.  PALMER

&&

.PRELIMINARY POINT TEMPS/POPS...
PENDLETON (AIRPORT) 37 27 36 / 50 60 40
WALLA WALLA         39 30 37 / 50 60 30
TRI-CITIES          40 31 39 / 50 50 20
YAKIMA              33 25 32 / 60 60 20
&&

.PDT WATCHES/WARNINGS/ADVISORIES...
OR...WINTER STORM WATCH TONIGHT FOR OREGON ZONES 46 AND 50.
WA...SNOW ADVISORY TODAY AND TONIGHT FOR WASHINGTON ZONES
     25. WINTER STORM WATCH TONIGHT FOR ZONE 30.
&&

82

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE PENDLETON OR
500 AM PST SAT DEC 27 2003

ORZ041>050-WAZ024>030-281302-

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

.DAY ONE...

THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW.

LIGHT SNOW IS EXPECTED TO DEVELOP TODAY ACROSS THE EAST SLOPES OF THE
WASHINGTON CASCADES AND CONTINUE INTO TONIGHT. 5 TO 8 INCHES OF SNOW
IS POSSIBLE AND A SNOW ADVISORY HAS BEEN ISSUED FOR THIS AREA THROUGH
TONIGHT. ALSO...A WINTER STORM WATCH IS IN EFFECT FOR THE BLUE AND
WALLOWA MOUNTAINS TONIGHT. LIGHT SNOW WILL DEVELOP TONIGHT THAT MAY
BECOME HEAVY AT TTMES. SNOW ACCUMULATIONS BETWEEN 5 TO 9 INCHES AND
WITH AN UPSLOPE FLOW...HIGHER AMOUNTS ARE POSSIBLE. ADDITIONAL
INFORMATION CAN BE FOUND UNDER THE FOLLOWING PRODUCT...PDXWSWPDT.

.DAYS TWO THROUGH SEVEN...

THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW.

ANOTHER STORM SYSTEM MAY AFFECT THE REGION SUNDAY THAT SHOULD
INCREASE SNOW CHANCES. SNOW ACCUMULATIONS ARE POSSIBLE MAINLY IN AREA
MOUNTAINS. THEN MUCH COLDER AIR WILL ENTRENCH THE TWO STATE AREA
MONDAY THROUGH THE MIDDLE OF THE WEEK BEFORE A SERIES OF STORMS
POUNDS THE PACIFIC NORTHWEST COAST INTO THE END OF THE WEEK.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE NEEDED TONIGHT AS A WINTER STORM WATCH HAS
BEEN ISSUED FOR THE BLUE AND WALLOWA MOUNTAINS WITH SIGNIFICANT
ACCUMULATIONS POSSIBLE.

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