Wildfire in Oregon, July 2 to 3, 2018

Area Forecast Discussion
National Weather Service Pendleton OR
233 PM PDT Mon Jul 2 2018

.SHORT TERM...Tonight through Thursday...Breezy to locally very
windy conditions will persist into the evening. Winds will decrease
towards midnight. The strongest winds will mainly be along the north
side of the Kittitas Valley where an advisory remains in effect.

An upper trough will swing across the Pacific Northwest tonight
through mid morning on Tuesday. This system will increase cloud
cover across our Washington and northern Oregon zones tonight. This
system may produce a few showers over the Northern Blue mountains
and portions of southeast Washington overnight through mid Tuesday
morning. Also may see a few showers near the Washington Cascade
crest tonight. A larger upper low is still expected to develop off
the PacNW coast Tuesday afternoon through Wednesday. Thus will see a
gradual shift in the winds aloft from westerly to southerly during
this period. As a result, should see fair and dry conditions with
warming temps. By Wednesday afternoon, high temps will run from
around 80 in the mountains to near 90 at the lowest elevations. This
upper low looks to remain off the PacNW coast Wednesday night and
Thursday, with the southerly flow continuing aloft. Temps will rise
a few more degrees Thursday. A weak wave is expected to move north
through Idaho late Wednesday night and Thursday morning. This wave
may cause a few showers over portions of Wallowa county at those
time periods. 90

.LONG TERM...Thursday night through Monday...Medium range models in
general agreement bringing the large ridge over the eastern CONUS
westward to the four corners region by the weekend. This will result
in the trough offshore OR/WA Thursday night to push north to
northeast and gradually weaken through the first half of the weekend.
Dry and warm conditions will prevail Thursday night/Friday in
advance of the approach of the trough. A shortwave rotating around
the trough is progged to cross the interior Pacific northwest Friday
night, exiting to the east on Saturday. Still some question about
how much tropical moisture is tapped from the decaying Hurricane
Fabio, but the latest trends show the additional moisture quite
limited. Will retain slight chance to low end chance PoPs as the
trough crosses. Low level instability is nearly non-existent Friday
afternoon into evening, with any elevated instability closer to the
trough axis across east-central and NE Washington overnight, thus
will keep thunderstorms out of the forecast. Dry conditions will
return area wide Saturday afternoon as the trough weakens and exits.
Dry conditions will prevail Sunday through early next week as the
region will be along the northern periphery of the large ridge to
the south. Seasonably warm condition can be expected Saturday, with
a gradual warmup through early next week, with highs Monday in the
lower to mid 90s across the lowest elevations.

&&

.AVIATION...00Z TAFs...VFR conditions will prevail for the next 24
hours, with mainly FEW-SCT cirrus clouds for most locations. Some
mid level clouds will impact ALW and possibly PDT late evening and
overnight, but do not expect any precip. Breezy to windy conditions
will prevail area wide through this evening, with gusts to 30-35 KT
likely at DLS/PDT, and gusts around 25 KT elsewhere. Winds will
decrease overnight to 8-15 KT. Winds will generally remain 12 KT or
less for Tuesday afternoon.

&&

.FIRE WEATHER...Red Flag Warnings remain in effect until 11 PM for
areas in and around the Columbia Basin down to Central Oregon,
including the southern Kittitas Valley, the Eastern Columbia River
Gorge, and the Prineville District. Winds are increasing with the
cold frontal passage with gusts to 25-35 mph in the warning area;
winds will diminish overnight. A warming trend is in store through
Thursday. Winds will be considerably less on Tuesday but will be
locally breezy from the north on Independence Day. The combination
of breezy winds and low RHs on Independence Day have warranted fire
weather watches for the Lower Columbia Basin, the Hanford District,
and Central Oregon. Conditions are more on the low end of the RFW
criteria but the human-caused fire threat on the holiday has been
taken into account. Any fires that develop could spread rapidly in
the grassy fuels. Wister

&&

.PRELIMINARY POINT TEMPS/POPS...
PDT  47  76  51  88 /  10  10   0   0
ALW  51  77  54  89 /  10  10   0   0
PSC  50  80  51  90 /  10  10   0   0
YKM  48  81  51  88 /  10  10   0   0
HRI  50  81  50  91 /  10  10   0   0
ELN  49  79  48  87 /  10  10  10  10
RDM  34  76  46  87 /   0   0   0   0
LGD  43  72  44  86 /   0  10   0   0
GCD  39  74  47  88 /   0   0   0   0
DLS  52  83  54  93 /  10  10   0   0

&&

.PDT WATCHES/WARNINGS/ADVISORIES...
OR...Red Flag Warning until 11 PM PDT this evening for ORZ610-639>641.

     Fire Weather Watch from Wednesday afternoon through Wednesday
     evening for ORZ640-641.

WA...Red Flag Warning until 11 PM PDT this evening for WAZ639-641-675.

     Fire Weather Watch from Wednesday afternoon through Wednesday
     evening for WAZ641-675.

     Wind Advisory until 8 PM PDT this evening for WAZ026.

&&

90/80/80/85