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fxus66 kpdt 170953 

Area forecast discussion
National Weather Service Pendleton or
253 am PDT Tue Jul 17 2018

Short through Thursday. Water vapor imagery shows
upper low moving out of the forecast area into Idaho. Some
lingering clouds that will be dissipating later this morning.
Otherwise another sunny hot day with highs in the 90s to 105. Heat
advisories remain in effect. Relative humidity cross sections show the airmass
becoming very dry by afternoon. Westerly winds will be increasing
and red flag warnings also remain in effect. A dry westerly flow
aloft over the region Wednesday and Thursday with mainly clear
skies. Temperatures will be gradually cooling over the next few
days. Highs Wed mostly in the 90s and for Thu upper 80s and 90s.
Surface gradients and westerly flow aloft will favor continued
breezy conditions each day. 94

Long term...Thursday night through Tuesday...Thursday night the
area will be under a westerly flow with high pressure over the
southwestern states and a upper low and trough approaching the
northern British Columbia coast. It should be a fair and dry night
with clear skies. Breezy winds are expected in the Columbia Gorge
and Kittitas Valley in the evening. Friday through Sunday the trough
will cross through British Columbia and into Alberta. A more
southwesterly flow will develop but the air mass will be so dry that
I do not see much in the way of clouds let alone showers or
thunderstorms. Temperatures Friday through Sunday will be fairly
consistent in the lower to mid 90s in the lower elevations and
mainly in 80s elsewhere. Pressure gradients along the Cascades will
be tight Friday and breezy winds will develop in the Kittitas
Valley, Columbia Gorge and central Oregon and with low humidities,
fire weather concerns may be heightened. Sunday night through
Tuesday the trough will move off to the east and a generally
westerly flow will resume over the area. Models show any moisture
circulating around the high pressure will remain to our south, so
continued dry and fair weather with mostly clear skies is
anticipated. High pressure will build northward slightly Monday and
Tuesday so temperatures will be increasing a degree or two each day
ending up in the mid 90s in the lower elevations and in the mid 80s
to lower 90s elsewhere. Perry


Aviation...12z tafs...VFR conditions are expected for the next 24
hours. Scattered clouds at or above 15k feet above ground level will continue over
the Columbia Basin this morning affecting kpsc, kalw and kpdt.
Otherwise skies will be mostly clear with no precipitation expected.
Winds will increase to 10 to 15 mph with gusts to 25 mph this
afternoon and evening before dropping below 10 kts after 05z. An
exception will be kdls which will reach 15 to 20 kts with gusts to
30 kts. Perry


Preliminary point temps/pops...
PDT 100 63 95 60 / 0 0 0 0
alw 102 65 96 62 / 0 0 0 0
psc 104 64 98 61 / 0 0 0 0
ykm 102 61 96 58 / 0 0 0 0
hri 104 65 98 62 / 0 0 0 0
eln 99 62 91 58 / 0 0 0 0
rdm 98 53 92 50 / 0 0 0 0
lgd 97 56 90 52 / 0 0 0 0
gcd 96 57 91 54 / 0 0 0 0
dls 98 63 91 59 / 0 0 0 0


PDT watches/warnings/advisories... flag warning from 1 PM this afternoon to 8 PM PDT Wednesday
for orz639.

Red flag warning from 4 PM this afternoon to 8 PM PDT Wednesday
for orz610-640-641.

Heat advisory until 9 PM PDT this evening for orz044-507. flag warning from 1 PM this afternoon to 8 PM PDT Wednesday
for waz639.

Red flag warning from 4 PM this afternoon to 8 PM PDT Wednesday
for waz675.

Heat advisory until 9 PM PDT this evening for waz026>029.

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