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Area forecast discussion 
National Weather Service Pendleton or
230 PM PDT sun Mar 29 2015

Short term...tonight through Wednesday. Southwest flow aloft
continues tonight into Monday. Middle and high level clouds will be
moving through at times with clear to partly cloudy skies. Low level
air mass will be a little warmer tomorrow so high temperatures up a few
degrees. Expect 60s to lower 70s. An upper level trough and cold
front will be approaching the Pacific northwest during the day. This
system will move through late Monday night and Tuesday. Expect a
period of rain with the frontal passage then scattered showers.
Fairly strong cold advection so much cooler with highs down about
10-15 degrees. West winds will be increasing becoming breezy to
windy during the day. Cold upper level trough over the region
Tuesday night and Wednesday with scattered rain and mountain snow
showers. 94

Long term...Wednesday night through unsettled and
progressive pattern will be over the Pacific northwest through the
long term period. Initially a trough will be over the area and a
weak disturbance will fall apart as it moves through the trough.
There will be a chance of mainly snow showers in the mountains and a
slight chance of rain showers in the lower elevations Wednesday night
followed by a chance of snow showers in the mountains Thursday while
the lower elevations are dry. Snow levels will be at 2500-3500 feet
at night and 3500-4500 feet during the day. This pattern will
continue through next weekend. Thursday night and Friday will be a
break between system though the will be a slight chance of upslope
rain and snow showers in the mountains. Friday night and Saturday an
upper low will carve a trough just off the coast and a moist
southwest flow will bring a chance of rain and snow showers to the
mountains and a slight chance of rain showers to the lower
elevations. By Sunday the GFS has the trough moving ashore while the
European model (ecmwf) has it still offshore. Have bumped up a few percent for the
entire area and gave all the area a chance of rain and mountain snow
showers in case the European model (ecmwf) is right. Highs will be near normal in the
middle 50s to lower 60s in the lower elevations and in the middle 40s to
middle 50s in the mountains. Lows will be mainly in the 30s and mainly
in the 20s in the mountains. Perry


Aviation...00z tafs...VFR conditions will continue for the next 24
hours. Ceilings will be scattered to broken above 15k feet though
some cumulus will develop over the mountains after 20z tomorrow
afternoon. Winds are expected to be generally below 12 kts for the
next 24 hours though krdm, kbdn and kdls will reach 10-15 kts with
higher gusts tomorrow afternoon. Perry


Preliminary point temps/pops...
PDT 42 69 44 57 / 0 0 10 40
alw 44 70 45 58 / 0 0 10 40
psc 41 72 46 62 / 0 0 10 30
ykm 40 68 42 58 / 0 0 20 30
hri 40 72 44 61 / 0 0 10 40
eln 38 67 40 55 / 0 0 20 30
rdm 34 69 38 50 / 0 0 20 40
lgd 36 68 40 52 / 0 0 10 50
gcd 33 71 34 51 / 0 0 10 40
dls 42 71 46 58 / 0 0 30 50


PDT watches/warnings/advisories...

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