Flood in Washington, March 10 to 11, 2017

Area Forecast Discussion...Updated
National Weather Service Pendleton OR
350 PM PST Fri Mar 10 2017

Updated aviation discussion

.SHORT TERM...A ridge of high pressure will build into the region
with mainly dry conditions expected into tonight except for the area
mountains that could experience an isolated shower. Despite some
patchy fog tonight the drier conditions will give way to a low
pressure system that will spread mid and high level clouds to the
region Saturday into Saturday night. Snow levels will remain high
and the pcpn should remain mostly liquid. The low pressure system
along with most of its moisture will move away from the area Sunday
with lingering showers once again in the area mountains into Sunday
night.

.LONG TERM...Monday through Friday...An upper ridge over the area
will get flattened and pushed east Monday and Monday night as a
system moves over the ridge. During the day there will be a chance
of rain in the mountains and a slight chance in the lower elevations
becoming a chance of rain across the area Monday night. Snow levels
will rise to above 8000 feet. The lower elevations will generally
see around a tenth of an inch of rain but the Blue Mountain
Foothills could see up to two tenths of an inch and the mountains up
to a half inch. Tuesday will see a chance of rain in the morning
before rain tapers off to showers in the afternoon. Tuesday night
will be a break between systems before another system arrives on
Wednesday with another chance of rain through Wednesday night. Snow
levels will remain above 7000 feet. A slight chance of showers will
linger in the mountains Thursday but otherwise Thursday and Thursday
night will be another break between systems. Models are in good
agreement in having another system arrive Friday with a chance of
rain across the area. Temperatures will be at or slightly above
seasonal norms with highs in the 50s and lower 60s Monday through
Wednesday then cooling to the upper 40s and 50s Thursday and Friday.
perry

&&

.AVIATION...00Z TAFs...VFR conditions will continue for the next 24
hours. Tonight will see scattered to broken cirrus above 15000 feet
AGL with few to scattered mid level clouds above 6000 feet AGL. The
next system will be approaching the area after 15Z with lowering
ceilings but showers will mainly hold off until after 18Z. All TAF
sites have -shra beginning 17-20Z and continuing through 00Z with
ceilings from 4000-7000 feet AGL. Winds are decreasing this
afternoon but 10-20 kt winds with gusts to 25 kts will continue at
all TAF sites except KRDM and KBDN for a few more hours. After 03Z,
winds will remain below 15 kts through 00Z tomorrow. Perry

&&

.HYDROLOGY...Previous days rain over northeast Oregon and southeast
Washington had increased runoff with small streams and creeks
running high and fast and a Flood Advisory remains in effect for
these areas today. In Central Washington there is still a low to mid
elevation snowpack and as warmer temperatures continue in this area
with periods of rain expected through the next 7 days we could see
some localized flooding for this area.

&&

.PRELIMINARY POINT TEMPS/POPS...
PDT  36  51  40  56 /   0  40  50  10
ALW  39  52  42  56 /   0  40  50  10
PSC  35  50  40  58 /   0  40  30  10
YKM  32  50  34  55 /   0  50  20  10
HRI  34  50  40  58 /   0  40  30  10
ELN  30  45  33  49 /   0  60  30  10
RDM  30  57  35  59 /   0  20  20  10
LGD  35  53  41  55 /   0  30  60  10
GCD  33  56  37  56 /   0  30  40  10
DLS  35  51  41  57 /   0  40  40  20

&&

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

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