Wind Advisory 18, NWS Pendleton, OR

996 
WWUS76 KPDT 300359
NPWPDT

URGENT - WEATHER MESSAGE
NATIONAL WEATHER SERVICE PENDLETON OR
859 PM PDT FRI APR 29 2016

...WINDS DECREASING IN THE KITTITAS VALLEY THIS EVENING...

.PRESSURE GRADIENTS ARE DECREASING AND WINDS ARE DECREASING IN
THE KITTITAS VALLEY TONIGHT.

WAZ026-300500-
/O.EXP.KPDT.WI.Y.0018.000000T0000Z-160430T0400Z/
KITTITAS VALLEY-
INCLUDING THE CITIES OF...ELLENSBURG...THORP
859 PM PDT FRI APR 29 2016

...WIND ADVISORY WILL EXPIRE AT 9 PM PDT THIS EVENING...

PRESSURE GRADIENTS ARE WEAKENING IN THE KITTITAS VALLEY THIS
EVENING. IN THE LAST HOUR OR TWO WINDS HAVE GENERALLY DROPPED TO
20 TO 30 MPH EXCEPT IN ONE OR TWO ISOLATED LOCATIONS AND ARE
EXPECTED TO CONTINUE DECREASING THE REST OF THE NIGHT. THEREFORE
THE WIND ADVISORY WILL BE ALLOWED TO EXPIRE AT 9 PM PDT AS
SCHEDULED.

$$

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
1035 AM PDT FRI APR 29 2016

.SHORT TERM...TODAY...TWO WEAK MID/UPPER LEVEL SYSTEMS WILL
AFFECT THE FORECAST AREA TODAY. A LOW IN THE IDAHO PANHANDLE AND
WESTERN MONTANA WILL SEND WRAP AROUND MOISTURE INTO SOUTHEAST
WASHINGTON AND NORTHEAST OREGON PRODUCING SHOWERS IN THE BLUE
MOUNTAINS AND THE WALLOWA MOUNTAINS. WALLOWA COUNTY WILL HAVE
MARGINAL INSTABILITY THIS AFTERNOON FOR A SLIGHT CHANCE OF
THUNDERSTORMS. THIS INSTABILITY RAPIDLY DIMINISHES BY 6 PM. THE
OTHER SYSTEM IS A SHORT WAVE MOVING SOUTHEAST INTO A SPLIT FLOW
ALOFT OVER CENTRAL OREGON TODAY. WEAK DYNAMIC LIFT ASSOCIATED WITH
THE SHORT WAVE WILL TRIGGER SHOWERS IN CENTRAL, NORTH CENTRAL AND
EAST CENTRAL OREGON THIS AFTERNOON WITH NUMEROUS SHOWERS DEVELOPING
OVER THE COLUMBIA DESCHUTES PLATEAU INCLUDING THE OCHOCO-JOHN DAY
HIGHLANDS. POLAN

.AVIATION...18Z TAFS. SCATTERED SHOWERS EXPECTED TODAY INTO THE
EVENING ASSOCIATED WITH AN UPPER LEVEL TROUGH MOVING THROUGH THE
REGION. CEILINGS 040-080. WESTERLY WINDS 10-25KT.

&&

.PREVIOUS DISCUSSION... /ISSUED 443 AM PDT FRI APR 29 2016/

SHORT TERM...TODAY THROUGH SATURDAY NIGHT...AN UPPER LOW OVER THE
IDAHO/MONTANA BORDER AREA EARLY THIS MORNING HAS BEEN PUSHING
MOISTURE AND SHOWERS INTO PORTIONS OF SOUTHEAST WASHINGTON AND
NORTHEAST OREGON. ONE BAND OF SHOWERS HAS BEEN PERSISTING FROM NEAR
CONNELL SOUTHEAST TO WALLA WALLA AND INTO NORTHERN UNION COUNTY.
EXPECT THIS BAND TO WEAKEN AND REDEVELOP TO THE EAST OVER EXTREME
SOUTHEAST WASHINGTON AND WALLOWA COUNTY. THUS WILL RUN HIGHER POPS,
50-60 PERCENT, OVER THESE AREAS INTO MID TO LATE MORNING. ANOTHER
DISTURBANCE WILL SWING SOUTHEAST ACROSS WESTERN WASHINGTON AND
WESTERN OREGON TODAY INTO THIS EVENING. THIS SYSTEM WILL KEEP
VARYING CHANCES OF SHOWERS GOING THROUGH THE AFTERNOON INTO THE
EVENING. BEST CHANCES WILL BE ALONG THE CASCADES AND OVER THE
EASTERN MOUNTAINS. CHANCES FOR THUNDERSTORMS STILL LOOK TO BE
LIMITED TODAY AND WILL CONTINUE TO INDICATE A SLIGHT CHANCE FOR
PORTIONS OF WALLOWA COUNTY AND THE OCHOCO-JOHN DAY HIGHLANDS LATE
THIS AFTERNOON. WINDS WILL BE BREEZY TO WINDY TODAY WITH THE
STRONGEST WINDS EXPECTED IN THE KITTITAS VALLEY. WINDS ALONG THE
NORTH SIDE OF THIS VALLEY MAY PUSH THE 30 MPH SUSTAINED RANGE. WILL
HOLD OFF ON ISSUING AN ADVISORY FOR THIS AREA DUE TO THE MARGINAL
NATURE OF THIS EVENT. AN UPPER LEVEL RIDGE WILL BUILD INTO THE
REGION LATE TONIGHT AND ON SATURDAY. THUS WILL SEE INCREASINGLY DRY
CONDITIONS WITH WARMING TEMPS SATURDAY. A FEW SHOWERS ARE EXPECTED
TO LINGER OVER OUR NORTHEASTERN MOST ZONES THROUGH SATURDAY.
CONDITIONS SHOULD BE DRY AREA WIDE SATURDAY NIGHT. 90

LONG TERM...SUNDAY THROUGH THURSDAY...HIGH PRESSURE WILL BUILD
IN OVER THE AREA FOR SUNDAY INTO MONDAY NIGHT. EXPECT WARM AND DRY
CONDITIONS DURING THIS TIME PERIOD.  THERE COULD BE SOME RESIDUAL
MOISTURE OVER SOUTHEAST GRANT AND SOUTHERN UNION COUNTY ON SUNDAY AS
THE PREVIOUS LOW DEPARTS TO THE SOUTHEAST.  SLIGHT CHANCE THUNDER
SUNDAY AFTERNOON AND EVENING MAY NEED TO BE ADDED TO THESE
AREAS...BUT FOR NOW WILL KEEP THE FORECAST DRY.

AS WE MOVE INTO MID WEEK...MODELS ARE IN PRETTY GOOD AGREEMENT WITH
THE RIDGE OF HIGH PRESSURE SLOWLY SHIFTING EASTWARD.  AT THE SAME
TIME A DEEP LOW PRESSURE SYSTEM IS EXPECTED TO SET UP OFF THE
CALIFORNIA COAST.  THIS WILL ENHANCE A WARM MOIST SOUTHERLY FLOW TO
THE AREA...INCREASING THE CHANCES FOR SHOWERS AND THUNDERSTORMS
ACROSS THE INTERIOR PACIFIC NORTHWEST.  BEST CHANCE SHOWER ACTIVITY
IS EXPECTED TO START ACROSS THE CASCADES AND CENTRAL OREGON AREA ON
TUESDAY...AND EXPAND IN COVERAGE ACROSS ALL AREAS BY WEDNESDAY INTO
THURSDAY.  THIS SCENARIO HAS A GOOD FETCH OF MOISTURE ALONG WITH
HIGH MODEL QPF...FAVORING SHOWERS AND THUNDERSTORMS WITH DECENT
WETTING RAIN POTENTIAL.  WILL CONTINUE TO MONITOR THE EXTENDED AND
MAKE ADJUSTMENTS AS THIS SYSTEM APPROACHES THE NEAR TERM.

HIGHS ACROSS THE LOWER ELEVATIONS LOOK TO BE IN THE MID 70S TO MID
80S FOR THE EXTENDED...AND IN THE MID 60S TO LOWER 70S FOR THE
MOUNTAINS. NORMALS FOR THIS TIME OF YEAR RANGE IN THE MID 60S TO
LOWER 70S FOR THE LOWER ELEVATIONS...AND IN THE UPPER 50S TO LOWER
60S MOUNTAINS. SO OVERALL SLIGHTLY ABOVE NORMAL TO WELL ABOVE NORMAL
TEMPERATURES EXPECTED FOR THE EXTENDED. WEBER

&&

.PRELIMINARY POINT TEMPS/POPS...
PDT  61  43  68  44 /  30  20  10   0
ALW  61  46  68  48 /  50  20  10   0
PSC  68  44  75  44 /  20  20  10   0
YKM  66  41  75  42 /  20  20   0   0
HRI  66  42  73  41 /  20  20   0   0
ELN  62  42  73  41 /  20  20   0   0
RDM  56  29  66  32 /  30  20   0   0
LGD  55  40  62  41 /  40  40  10   0
GCD  56  36  65  37 /  50  40  10   0
DLS  63  45  74  45 /  20  20   0   0

&&

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

FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON

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