Severe Thunderstorm Warning 22, NWS Pendleton, OR

NORTHEAST OREGON/SOUTHEAST WASHINGTON FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
215 PM PDT TUE AUG 5 2003

STRONG CONVECTION DEVELOPING AHEAD OF A DISTURBANCE LOCATED OVER
SOUTHWEST OREGON WILL CONTINUE TO MOVE NORTH THROUGH OUR WESTERN CWA
OVERNIGHT. LIFT AND INSTABILITY AHEAD OF THIS SYSTEM WILL CONTINUE
TO AID IN THE PRODUCTION OF STRONG THUNDERSTORMS THROUGH THIS
EVENING...SOME WILL LINGER THROUGHOUT THE NIGHT OVER PORTIONS OF THE
MOUNTAINS. INSTABILITY WILL CONTINUE OVER THE MOUNTAINS AS THE MAIN
TROUGH ANCHORS ITSELF OVER THE EASTERN PACIFIC. AS A
RESULT...ISOLATED MOUNTAIN THUNDERSTORMS ARE EXPECTED TO REDEVELOP
EACH AFTERNOON THROUGH FRIDAY AS WEAK DISTURBANCES ROTATE AROUND THE
MAIN LOW. TEMPERATURES ARE EXPECTED TO STAY NEAR NORMAL.

EXTENDED...UPPER TROUGH TO REMAIN OVER THE EASTERN PACIFIC WITH A
SOUTHWEST FLOW CONTINUING OVER THE PACIFIC NORTHWEST INTERIOR
THROUGH THE WEEKEND. THERE SHOULD BE ENOUGH LINGERING MOISTURE FOR
THE DEVELOPMENT OF A FEW SHOWERS OR THUNDERSTORMS FRIDAY. STILL
APPEARS THAT LOW LEVEL ONSHORE FLOW WILL STRENGTHEN OVER THE
WEEKEND. THIS WOULD RESULT IN THE AIR MASS OVER OUR CWA TO STABILIZE
WITH NO SHOWERS AND THUNDERSTORMS EXPECTED. MID RANGE MODELS ARE
PROVIDING SOME VARIANCE IN SOLUTIONS...BUT SUPPORT CONTINUES FOR THE
UPPER TROUGH TO SLOWLY DRIFT EAST-SOUTHEAST EARLY NEXT. IF THE
TROUGH DOES DRIFT INLAND...THIS COULD LEAD TO A RETURN TO A LOW
CHANCE OF SHOWERS OR THUNDERSTORMS MONDAY AND TUESDAY OVER THE
MOUNTAINS. GKH

PDT 4---  ALW 4---  PSC 3---  YKM 3---

.KPDT...NONE.

ORZ041>050-WAZ024>030-061200-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE PENDLETON OR
422 AM PDT TUE AUG 5 2003

.DAY ONE...TODAY

AN UPPER PACIFIC LOW PRESSURE SYSTEM WILL MOVE INTO A MOIST AND
UNSTABLE AIR MASS OVER THE REGION TODAY AND TRIGGER WIDESPREAD
THUNDERSTORMS ACROSS EASTERN OREGON AND SOUTHEAST WASHINGTON. SOME
OF THESE STORMS MAY BECOME SEVERE WITH STRONG DAMAGING WINDS...LARGE
HAIL...HEAVY RAIN AND FREQUENT DANGEROUS LIGHTNING.

.DAYS TWO THROUGH SEVEN...

THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW.

A MOIST SOUTHWEST FLOW PATTERN ALOFT WILL CONTINUE THROUGH THE
PERIOD. HOWEVER THE ATMOSPHERE WILL BE MORE STABLE WITH LESS SHOWER
AND THUNDERSTORM ACTIVITY EXPECTED.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION WILL BE LIKELY.

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

RSC

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE PENDLETON OREGON
225 PM PDT TUE AUG 05 2003

TIME(PDT)  .....CITY LOCATION.....STATE   ...EVENT/REMARKS...
           ....COUNTY LOCATION....

0219 PM    CULVER                    OR   .88 INCH HAIL
08/05/03   JEFFERSON                      REPORTED BY STORM
                                          SPOTTER.