Wildfire in Washington, June 22 to 23, 2018

Area Forecast Discussion...Updated
National Weather Service Pendleton OR
417 AM PDT Fri Jun 22 2018

Updated Aviation Discussion

.SHORT TERM...Today through Sunday...A weather system that brought
rain and thunderstorms during the past 24 to 36 hours is moving east
and will be replaced by a building high pressure ridge aloft today.
The main concern for today will be increasing winds through the gaps
and passes of the Cascade range...especially the eastern Columbia
River Gorge and the Kittitas Valley. Winds in the Kittitas Vally
will be close to wind advisory criteria and slightly less in the
gorge. Will evaluate further and decide if the winds will get strong
enough for a wind advisory, otherwise will pass it along to the day
shift to monitor it. Today will be substantially cooler than the
past 2 days with readings in the lower elevations in the 80s rather
than the lower to mid 90s. This will be mostly due to the mixing
effects of the increasing winds that are expected today. Pressure
gradients will become the tightest this afternoon. The winds will
diminish late tonight or early Saturday morning...but slowly.
Pressure gradients will continue to relax on Saturday. However,
temperatures on Saturday will be even a couple more degrees cooler.
Then on Sunday the upper ridge becomes more amplified with the ridge
axis moving across the Pacific Northwest which will result in a
moderate warming trend again and temperatures in the lower
elevations back into the lower to mid 90s again. The short term
forecast period will be dry, except a few possible light showers
over the Washington Cascades late this afternoon and tonight mainly
caused by upslope and a very minor weak short wave in the flow. It
will then remain dry through the rest of the short term forecast
period. 88

.LONG TERM...Sunday night through Friday...A ridge of high pressure
will weaken and shift east Sunday night with a cold front
approaching the Pacific Northwest. The cold front arrives in our
area Monday morning with a slight chance of showers to the
Washington Cascades Monday morning with breezy conditions developing
by afternoon behind the front. Flow becomes zonal behind the
departing cold front beginning Tuesday and remains so through at
least Wednesday night with dry westerly flow over the region. Models
begin to diverge in handling of deepening trough over the western US
toward the end of the week with the ECMWF a little deeper than the
GFS. Have kept a slight chance of showers, mostly in the mountains
for Friday giving some weight to the ECMWF solution. Temperatures in
the lower elevations will be near normal...mid 70s to lower 80s
through the period. Peck

&&

.AVIATION...12Z TAFS...Breezy winds expected at all sites late this
morning into this evening as high pressure builds in west of the
Cascades with mostly clear skies. The strongest winds can be
expected at DLS and PDT. Peck

&&

.PRELIMINARY POINT TEMPS/POPS...
PDT  82  54  81  55 /   0   0   0   0
ALW  85  56  82  58 /   0   0   0   0
PSC  88  58  85  58 /   0   0   0   0
YKM  83  53  84  56 /   0   0   0   0
HRI  87  57  85  57 /   0   0   0   0
ELN  76  54  80  54 /   0   0   0   0
RDM  81  46  79  47 /   0   0   0   0
LGD  79  49  73  49 /   0   0  10  10
GCD  79  47  73  49 /   0   0   0   0
DLS  79  57  83  58 /   0   0   0   0

&&

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

88/74/74