Severe Thunderstorm Warning 9, NWS Pendleton, OR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OREGON
805 PM PDT SAT JUN 26 2004

.SHORT TERM...IT TOOK A WHILE BUT THUNDERSTORMS HAD DEVELOPED OVER
EASTERN WALLOWA COUNTY AS A THE IR SATL SHOWED A WEAK SHORT WAVE
ROTATING ACROSS THE AREA THAT COMBINED WITH SFC DEW POINTS NEAR 60F.
ONE STORM BECAME SEVERE WITH ECHO TOPS SOARING OVER 50K.
ALSO...SOME THUNDERSTORMS DEVELOPED BRIEFLY OVER EXTREME SE GRANT
COUNTY AND PUSHED EAST.

LATEST RADAR WAS SHOWING A HUGE AREA OF CONVECTION JUST SOUTH OF
BAKER COUNTY THAT WAS DRIFTING NORTH. THE FORECAST MODEL CONVECTIVE
PARAMETERS WERE SUGGESTING THAT SOME OF THIS MOISTURE WILL DRIFT
NORTH AND WITH A WEAK UPPER LEVEL JET APPROACHING...THIS MAY KEEP
CONVECTION FIRING OVER THE WALLOWA AREA EVEN AFTER SUNSET. WILL MAKE
MINOR ADJUSTMENTS TO THE EVENING WORDING OF ZONES LATER. OTHERWISE
THE FORECAST APPEARS ON TRACK FOR NOW.

&&

.PRELIMINARY POINT TEMPS/POPS...
PENDLETON (AIRPORT) 60 86 56 86 / 20 05 05 05
WALLA WALLA         61 86 58 86 / 20 05 05 05
TRI-CITIES          60 88 56 88 / 05 05 05 05
YAKIMA              63 84 59 84 / 10 05 05 05
&&

.PDT WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
&&

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE PENDLETON OREGON
510 AM PDT SAT JUN 26 2004

ORZ041>050-WAZ024>030-271200-
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-
510 AM PDT SAT JUN 26 2004

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

.DAY ONE...TODAY AND TONIGHT

SLIGHT RISK OF SEVERE THUNDERSTORMS
     FOOTHILLS OF THE BLUE MOUNTAINS (WA), NORTHWEST BLUE MOUNTAINS,
     FOOTHILLS OF THE BLUE MOUNTAINS (OR), BLUE MOUNTAINS, GRANDE
     RONDE VALLEY, WALLOWA COUNTY

THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS TODAY AND TONIGHT
NORTH AND EAST OF A LINE FROM UNION TO MEACHAM TO WALLA WALLA.
THIS INCLUDES THE CITIES OF WESTON...MILTON-FREEWATER...
DAYTON...BLUEWOOD SKI RESORT...UNION...ENTERPRISE...AND IMNAHA. THE
MAIN THREATS FROM THESE STORMS WILL BE LARGE HAIL...WINDS GUSTING TO
60 MPH...AND HEAVY RAIN.

GENERAL THUNDERSTORMS
     EAST SLOPES OF THE SOUTHERN CASCADES, KITTITAS VALLEY, YAKIMA
     VALLEY, LOWER COLUMBIA BASIN (WA), LOWER COLUMBIA BASIN (OR),
     FOOTHILLS OF THE BLUE MOUNTAINS (OR), JOHN DAY BASIN,
     OCHOCO-JOHN DAY HIGHLANDS

A LARGE LOW PRESSURE SYSTEM OFF THE EASTERN PACIFIC WILL EDGE
TOWARDS THE COAST AND WILL SPREAD MID LEVEL MOISTURE EAST OF THE
CASCADES.  THE AIR MASS IS ALREADY UNSTABLE...AND SCATTERED
THUNDERSTORMS WILL DEVELOP TODAY AND TONIGHT OVER THE
EASTERN MOUNTAINS WITH ISOLATED SHOWERS AND THUNDERSTORMS ELSEWHERE.

.DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY

THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW.

ISOLATED SHOWERS AND THUNDERSTORMS ARE EXPECTED SUNDAY THROUGH
WEDNESDAY.  THE UPPER LOW WILL MOVE INTO BRITISH COLUMBIA...LEAVING
THE PACIFIC NORTHWEST UNDER A FAIRLY MOIST SOUTHERLY FLOW ALOFT. A
DRIER WESTERLY FLOW IS EXPECTED LATE IN THE WEEK.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE REQUIRED.

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