Severe Thunderstorm Warning 2, NWS Pendleton, OR

NORTHEAST OREGON/SOUTHEAST WASHINGTON FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
420 PM PDT WED APR 16 2003

...CORRECTED TYPO...

ISOLATED AND SCATTERED SHOWERS ARE DEVELOPING THIS AFTERNOON ACROSS
THE AREA.  THESE SHOWERS WILL TAPER OFF AFTER THE SUN GOES
DOWN...AND DAYTIME HEATING STOPS.  A COLD FRONT IS DROPPING THE
SOUTH DURING THE OVERNIGHT HOURS INTO THE PACIFIC
NORTHWEST...BRINGING ANOTHER ROUND OF SHOWERS TO THE AREA.  THE COLD
FRONT WILL CROSS OVER THE CASCADES THE DURING THE EARLY MORNING
HOURS AND MOVE THROUGH OUR COUNTY WARNING AREA BY MID AFTERNOON.
ISOLATED THUNDERSTORMS WILL BE POSSIBLE IN THE NORTHEAST PORTION OF
THE STATE...AS INSTABILITIES INDICES COME INTO LINE ALONG WITH THE
POTENTIAL VORTICITY ADVECTION AND THE DIVERGENCE OF Q.  WINDS WILL
ALSO BE BECOMING BREEZY TO WINDY AS THE COLD FRONT MOVES THROUGH THE
AREA WITH THE STRONGEST WINDS OCCURRING WITH THE TIGHTEST PRESSURE
GRADIENTS DURING THE LATE AFTERNOON AND EVENING HOURS.  THESE WINDS
WILL ALSO CAUSE RAIN SHADOWING ACROSS MOST THE EAST SLOPES OF THE
CASCADES AND THE COLUMBIA RIVER BASIN.  THE WINDS WILL GRADUALLY
TAPER OFF DURING THE OVERNIGHT HOURS AND WE WILL ALSO BE DRYING OUT
DURING THE OVERNIGHT HOURS AS THE TROUGH AXIS MOVES THROUGH THE
REGION.  A RIDGE BEGINS TO BUILD INTO THE PACIFIC NORTHWEST ON
FRIDAY...WITH A WARM FRONT MOVING UP THE COAST.  WE WILL REMAIN
UNDER THE DRY SECTOR OF THE RIDGE...WITH SLIGHTLY WARMER IN
TEMPERATURES AND SOME HIGH CLOUD COVER.  PALMER

DAYS 3-7...CLOUDS WILL INCREASE AND THERE WILL BE A SLIGHT CHANCE OF
PRECIP MOVING INTO SOUTHERN WASHINGTON CASCADES ON SATURDAY AS A
HIGH PRESSURE RIDGE SHIFT EAST AHEAD OF THE NEXT WEATHER SYSTEM.  A
COLD FRONT WILL SWEEP THROUGH SATURDAY NIGHT AND SUNDAY...SPREADING
PRECIP ACROSS THE AREA.  SHOWERS WILL LINGER OVER THE REGION INTO
MONDAY AS THE TROUGH AXIS AND A COUPLE OF WEAK IMPULSES MOVE
THROUGH THE PACIFIC NORTHWEST.  A QUICK TRANSITORY RIDGE WILL SLIDE
ACROSS THE AREA ON TUESDAY...LIMITING PRECIP CHANCES.  THE NEXT
SYSTEM WILL BE APPROACHING THE AREA ON WEDNESDAY...TIMING IS
QUESTIONABLE BUT WILL INTRODUCE A SLIGHT CHANCE OF PRECIP MAINLY
ALONG WESTERN ZONES.  MJB.

PDT 2300  ALW 2300  PSC 2200  YKM 2200

.KPDT...NONE.

ORZ041>050-WAZ024>030-171300-

HAZARDOUS WEATHER OUTLOOK...UPDATED FOR THURSDAY WEATHER...
NATIONAL WEATHER SERVICE PENDLETON OR
500 AM PDT WED APR 16 2003

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

.DAY ONE...TODAY

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

A COUPLE OF WEAK DISTURBANCES...ROTATING AROUND A LARGER SYSTEM OFF
SHORE...WILL MOVE THROUGH THE EASTERN HALF OF OREGON AND WASHINGTON
TODAY. THIS WILL ALLOW FOR ISOLATED TO SCATTERED SHOWERS AND
THUNDERSTORMS TO DEVELOP ACROSS CENTRAL AND NORTHEASTERN OREGON.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

AN UPPER LEVEL DISTURBANCE WILL PUSH A COLD FRONT THROUGH SOUTHEAST
WASHINGTON AND CENTRAL AND NORTHEAST OREGON ON THURSDAY FOR
SCATTERED SHOWERS. EXPECT WINDY CONDITIONS TO DEVELOP THURSDAY
AFTERNOON AND NIGHT AS UPPER LEVEL WINDS MIX DOWN TO THE SURFACE AND
ADD TO THE GRADIENT WINDS.

.SPOTTER INFORMATION STATEMENT...

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