Wind Advisory 14, NWS Pendleton, OR

Area Forecast Discussion
National Weather Service Pendleton OR
524 PM PDT Fri Apr 27 2018

.UPDATE...Breezy west winds had developed into windy conditions
that expanded in areal coverage and the forecast was upgraded to
reflect this in and around the basin. Patchy blowing dust was also
added and the short term forecast into this evening is now more on
track. A low pressure system is approaching the region with
showers and isolated thunderstorms persisting into this evening as
well.

&&

.PREV DISCUSSION... /issued 224 PM PDT Fri Apr 27 2018/

SHORT TERM...Tonight through Sunday night...An upper low, currently
centered near 41N/129W, will continue to wobble northeast towards
the central Oregon coast tonight into Saturday morning. Moisture is
wrapping north along the eastern and northern sides of this low. As
a result expect varying coverages of showers to continue to develop
over the area this afternoon and evening. A few thunderstorms may
also develop, with portions of Grant, Union and Wallowa counties
having the best chances. Instability and shear are weaker than
originally expected, but a local strong gust with these storms can
not be completely ruled out. Overnight, a band of steadier showers
should develop over northeast Oregon, northwest across the
Washington Basin into Kittitas county. This band will gradually
drift north into northern Washington and Idaho by mid morning
Saturday. There is the outside chance of stray rumbles of thunder
within this band, but confidence is low and will not mention in the
afternoon forecast package. The upper low will move onshore Saturday
afternoon, then it will weaken as it drifts east across the region
Saturday night through Sunday night. With the upper low over the
region, can expect to see cooler and unsettled conditions Saturday
night through Sunday night. The best chances of showers will be over
the higher terrain. Also a few thunderstorms may develop over the
interior mountains in the afternoons and evenings. 90

LONG TERM...Monday through Friday...Upper level low pressure will
exit the area Monday/Monday night, with residual chances of showers
across the eastern mountains decreasing. Dry northerly flow will
develop Tuesday, with models in agreement Wednesday/Thursday
depicting strong ridging across the interior Pacific Northwest. For
Friday, GFS/ECMWF continue to be in poor agreement, with the GFS
breaking down the ridge and developing more moist southwest flow.
The ECMWF keeps the ridge overhead, with the 12Z ECMWF showing some
amplification of the ridge. Given the differences, will make little
changes to the Friday forecast keeping dry conditions area wide.
Near normal temperatures Monday will warm to slightly above normal
for Tuesday, with temperatures 10-15 degrees above normal for
Thursday and Friday under the strong ridge.

AVIATION...00Z TAFS...VFR conditions will prevail for the next 24
hours. Clouds will continue to lower and thicken late this
afternoon, with mid deck clouds area wide this evening. A broken
band of showers across central OR late this afternoon will become
more organized and move north into northern OR this evening,
eventually moving across southern WA overnight, exiting to the north
by Saturday morning. Local MVFR will be possible in the heavier
showers, but coverage of restrictions not sufficient to put into the
TAFs. Isolated thunderstorms will develop across the highlands of
central and eastern OR, but will remain away from the TAF sites.
After a period of dry conditions area wide Saturday morning, another
round of showers can be expected across central OR Saturday
afternoon. Breezy to windy winds will prevail through this evening,
with sustained winds of 15-25 KT with gusts to 35 KT possible,
especially at DLS/PDT/PSC. Winds will gradually diminish overnight,
with breezy conditions likely redeveloping Saturday afternoon.

&&

.PRELIMINARY POINT TEMPS/POPS...
PDT  46  64  45  63 /  60  10  20  20
ALW  49  66  46  65 /  70  20  20  20
PSC  52  70  46  69 /  60  10  10  10
YKM  48  69  44  69 /  40  10  10  10
HRI  49  68  46  68 /  40  10  10  20
ELN  47  63  43  63 /  60  20  10  10
RDM  33  57  34  57 /  20  40  40  30
LGD  47  60  39  57 /  80  40  40  30
GCD  40  58  38  55 /  60  50  50  40
DLS  48  66  47  65 /  60  20  20  20

&&

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

97/