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000
FXUS66 KPDT 162220 AAA
AFDPDT

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE PENDLETON OR
320 PM PDT WED APR 16 2014

UPDATED FOR AVIATION DISCUSSION

.SHORT TERM...TONIGHT THROUGH SATURDAY...THE NEXT PACIFIC SYSTEM
CONTINUES TO MOVE EAST ACROSS THE EASTERN PACIFIC THIS AFTERNOON
WITH THE MAIN ENERGY PUSH BETWEEN 45 AND 50 NORTH LATITUDE. WILL
CONTINUE TO SEE WARM AIR ADVECTION TONIGHT, PRODUCING MOSTLY MID AND
HIGH LEVEL CLOUDINESS. LIGHT PRECIP CAN BE EXPECTED AT TIMES ALONG
AND NEAR THE CASCADE CREST, WITH A FEW SPRINKLES POSSIBLE OVER THE
BLUE AND WALLOWA MOUNTAINS. THE CENTER OF THIS NEXT PACIFIC SYSTEM
WILL MOVE INTO CENTRAL BRITISH COLUMBIA THURSDAY. THE SYSTEM`S COLD
FRONT WILL SWING ACROSS THE PACNW LATE THURSDAY MORNING AND THURSDAY
AFTERNOON. AS SUCH, EXPECT MOST AREAS TO SEE PRECIP AS THIS COLD
FRONT MOVES THROUGH THE AREA. THERE MAY BE SOME WEAK INSTABILITY
ALONG THE FRONT LATE THURSDAY AFTERNOON THAT COULD CAUSE STRAY
THUNDERSTORMS. THE PORTION OF OUR AREA THAT MAY BE AFFECTED BY THIS
WEAK INSTABILITY IS SO SMALL I WILL NOT MENTION THUNDER THIS TIME. A
POOL OF COLD AIR ALOFT LOOKS TO SWING ACROSS WASHINGTON THURSDAY
NIGHT. THIS COLD AIR ALOFT MAY HELP KEEP SHOWERS GOING OVER PORTIONS
OF THE AREA, BUT INSTABILITY FOR POTENTIAL THUNDER WILL BE VERY
LIMITED DUE TO NIGHTTIME SURFACE COOLING. UPSLOPE AFFECTS OVER THE
INTERIOR MOUNTAINS WILL BE THE MAIN PRECIP PRODUCER IN OUR AREA
THURSDAY NIGHT. BREEZY WINDS WILL BE POSSIBLE BEHIND THE COLD FRONT
THURSDAY NIGHT. THESE WINDS WILL LAST INTO FRIDAY. PRECIP CHANCES
WILL COME TO AN END FRIDAY MORNING AS DRIER AIR MOVES INTO THE AREA.
WEAK HIGH PRESSURE WILL KEEP THE REGION DRY FRIDAY NIGHT INTO
SATURDAY, THOUGH ANOTHER PACIFIC SYSTEM MAY BEGIN TO PUSH SOME LIGHT
PRECIP TO THE CASCADE CREST AREA LATE SATURDAY AFTERNOON. 90

.LONG TERM...SATURDAY NIGHT THROUGH WEDNESDAY...WEST TO SOUTHWEST
FLOW WILL SET IN SATURDAY NIGHT THROUGH MONDAY NIGHT AS THE UPPER
LEVEL RIDGE BEGINS TO BREAK DOWN. FLOW WILL START OFF WESTERLY AND
WILL TRANSITION TO SOUTHWEST. PRECIPITATION CHANCES ARE NOT THAT
GREAT THROUGH SUNDAY NIGHT...EXCEPT ALONG THE EAST SLOPES OF THE
WASHINGTON CASCADES. BY MONDAY A LOW PRESSURE SYSTEM OFF THE COAST
WILL SPIN UP MOISTURE WITH THE SOUTHWEST FLOW...INCREASING POPS
ALONG THE NORTHEAST MOUNTAINS...AND BRINGING A SLIGHT CHANCE ACROSS
THE LOWER ELEVATIONS. BY MONDAY EVENING SHOWERS WILL BECOME LIKELY
ALONG THE NORTHEAST MOUNTAINS...AND THERE MAY EVEN BE SOME THUNDER
ASSOCIATED. DUE TO LACK OF MODEL CONSISTENCY...HAVE HELD OFF ON THE
MENTION OF THUNDER IN THE FORECAST. AS THE LOW MOVES OVER THE
FORECAST AREA ON TUESDAY THERE WILL STILL BE A CHANCE FOR
SHOWERS...BUT EXPECT TEMPERATURES TO COOL OFF WITH THE COLD FRONTAL
PASSAGE. OVERALL TEMPERATURES IN THE EXTENDED WILL START OUT IN THE
UPPER 60S TO LOWER 70S ACROSS THE LOWER ELEVATIONS...WITH 50S TO
LOWER 60S MOUNTAINS. THESE TEMPERATURES WILL INCREASE A DEGREE OR
TWO EACH DAY...UNTIL THE COLD FRONT PUSHES THROUGH ON TUESDAY...IN
WHICH THE TEMPERATURES ACROSS THE LOWER ELEVATIONS WILL BE BACK IN
THE LOWER TO MID 60S...WITH UPPER 40S TO UPPER 50S MOUNTAINS. WEBER

&&

.AVIATION...00Z TAFS...VFR CONDITIONS ARE FORECAST FOR THE NEXT 12
HOURS WITH POSSIBLE MVFR CONDITIONS STARTING AT KDLS AND KYKM 12-18
HOURS OUT...FOLLOWED BY THE REST OF THE TAF SITES IN THE LAST 6
HOURS OF THE TAF PERIOD. CIGS WILL RANGE FROM 5000-10,000 FEET AGL
FOR THE REST OF THIS EVENING.  CIGS WILL BEGIN TO LOWER OVERNIGHT
AND INTO THE EARLY MORNING HOURS AS A WARM FRONT...WITH STRATIFORM
PRECIPITATION MAKES ITS WAY ACROSS THE AREA.  EXPECT MVFR CIGS AND
VISIBILITIES FOR THE SECOND HALF OF THE TAF PERIOD.  IFR CONDITIONS
CAN`T BE RULED OUT...BUT CONFIDENCE IS NOT HIGH ENOUGH TO INCLUDE
THEM IN THE TAFS.  WINDS WILL GENERALLY BE 5 TO 15 KNOTS THROUGH THE
PERIOD. WEBER

&&

.PRELIMINARY POINT TEMPS/POPS...
PDT  43  61  41  59 /  10  70  80  10
ALW  47  62  44  60 /  10  70  80  10
PSC  45  63  42  65 /  10  60  60  10
YKM  44  61  37  63 /  20  50  20  10
HRI  43  63  41  64 /  10  60  60  10
ELN  44  58  39  60 /  20  60  30  10
RDM  38  60  28  61 /   0  60  30  10
LGD  37  63  39  57 /  10  40  80  20
GCD  36  65  36  59 /  10  40  70  10
DLS  47  62  43  64 /  20  60  30  10

&&

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

THREAT INDEX
THURSDAY : GREEN
FRIDAY : GREEN
SATURDAY : GREEN

GREEN: NONE OR LIMITED NEED FOR WATCHES, WARNINGS, OR ADVISORIES.
YELLOW: A FEW WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
RED: NUMEROUS WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.

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

$$

90/89/89