Upper level ridging and persistent surface high pressure in the Columbia Basin resulted in several areas reaching or exceeding critical heat risk thresholds during this period, with some mountain sites also seeing consecutive days of 95 degrees or greater temperatures.
Every event with a place to put it; 4 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS PDT wrote it up.
Upper level ridging and persistent surface high pressure in the Columbia Basin resulted in several areas reaching or exceeding critical heat risk thresholds during this period, with some mountain sites also seeing consecutive days of 95 degrees or greater temperatures.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Pendleton, OR wrote its last area forecast discussion before the first event at Aug 16, 7:40 PM PST, 4 hours 20 minutes earlier.
Area Forecast Discussion
National Weather Service Pendleton OR
840 PM PDT Tue Aug 16 2022
.UPDATE...High pressure is forecast to dominate the areas weather
with dry conditions and hot temperatures for the remainder of the
week. Afternoon high temperatures across the Columbia Basin are
expected to climb toward 100 degrees and higher and a heat
advisory remains in effect for a large part of the region into
Friday.
Meanwhile high pressure just to our east will remain nearly
stationary and some moisture may rap around and into portions of
central Oregon tomorrow afternoon that could produce an isolated
thunderstorm.
Otherwise minor changes were done to sky and overnight
temperatures tonight and the present short term forecast appears
on track.
&&
.PREV DISCUSSION... /issued 445 PM PDT Tue Aug 16 2022/
SHORT TERM...The main challenges with the short-term forecast
revolve around a couple shortwaves anticipated to ride around the
upper-level ridge on Wednesday and Thursday. The first of these
waves is currently visible off the northern California coast on
water vapor imagery. Monsoonal moisture transport up the back side
of the ridge will reach central Oregon and the Cascade crest
Wednesday morning and afternoon. This moisture, combined with
some weak synoptic lift from the shortwaves may facilitate
elevated showers and isolated thunderstorms for the central Oregon
Cascades, central Oregon, and Ochocos Wednesday afternoon.
Overnight into Thursday, guidance advertises another vorticity
maximum moving onshore and forming a weak mid-level low. The
current track is forecast to move southwest to northeast across
eastern Oregon or northern Nevada, though guidance is still
struggling with this feature. Thus, while additional lift will be
provided by the low, confidence in exact placement of showers and
isolated thunderstorms is low for Thursday afternoon into
Thursday night. The majority of the moisture is anticipated to
push along the Cascade crest Thursday, with perhaps some spilling
into the rest of eastern Oregon Thursday evening and night. Have a
slight chance of thunderstorms forecast for the Cascade crest on
Thursday, as this is where the best instability and moisture is
expected.
The other concern for Wednesday and Thursday will be very hot
temperatures for much of our CWA. Widespread highs in the 95-105
range are forecast Wednesday, and multiple Heat Advisories will be
in effect Wednesday morning through Friday evening. Thursday, more
uncertainty surrounds afternoon temperatures with potential mid-
level cloud cover due to the monsoonal moisture and potential
convective debris from any activity on Wednesday. Highs in the
95-105 range are still forecast, but these may come down a few
degrees should cloud cover inhibit daytime heating. Regardless,
advisory level heat will likely continue through the short term.
Plunkett/86
LONG TERM...Friday through Tuesday...Upper ridge will continue to
weaken as an upper trough off the coast tries to move into the
region. The forecast area will be in the saddle between the upper
ridge to the east and the upper trough off the coast to the
northwest, and another upper ridge to the southwest along the CA
coast. There will be some weak instability, but very little
moisture, so Friday looks to be dry. However, cannot rule out an
isolated weak thunderstorm over Wallowa County, but the chances
are very small, with low confidence. Temperatures still look to be
in the upper 90s to lower 100s in the lower elevations and mostly
80s to lower 90s mountains on Friday. Friday night and Saturday,
the upper trough off the coast and the upper ridge over Montana
will cause a southwest to west flow over the forecast area. There
will also be a subtle upper low over the great basin, but that
will have no effect on the weather in the CWA. Therefore, at this
time, it looks to remain dry through Saturday night into early
Sunday. However, the upper trough off the coast is now forecast by
both the ECMWF and GFS to move into the region and forecast area
by Sunday afternoon. This will result in a slight chance of
thunderstorms over mainly the Elkhorn and Wallowa Mountains.
However, elsewhere it will stay dry. A slight chance of
thunderstorms will persist Sunday evening, and then dissipate
overnight. There may still be a few showers, mainly over Wallowa
County and the northern Blue Mountains Sunday night and Monday
morning. Then with afternoon heating on Monday, combined with the
upper trough that will still be moving across the region, there
will be another slight chance of thunderstorms over Wallowa
County. Then on Tuesday, a drier northwest flow will develop
behind the trough as it departs the region. Tuesday looks to be
dry. Temperatures on Monday and Tuesday will be cooler, with highs
in the 90s in the lower elevations, and mid 70s to mid 80s
mountains. While these temperatures are still above normal, it
will feel cooler compared to the triple digit heat in the short
term and in the early long term forecast period.
It will be breezy to windy in the eastern Columbia River
Gorge/north central OR area, as well as possibly the Kittitas
Valley Friday afternoon and evening. After that winds look to be
mostly light, except for the usual locations where winds tend to
increase during the afternoons and evenings, such as the eastern
Columbia Gorge and Kittitas Valleys.
AVIATION...vfr conditions are expected to continue for the next
24 hours. Winds are forecast to remain between 5 to 20 mph.
Meanwhile taf sites krdm and kbdn may experience few-sct100 after
20z.
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 61 101 65 99 / 0 0 0 0
ALW 63 104 67 102 / 0 0 0 0
PSC 64 104 68 103 / 0 0 0 0
YKM 60 101 67 103 / 0 0 0 0
HRI 62 105 67 103 / 0 0 0 0
ELN 60 102 66 103 / 0 0 0 0
RDM 56 99 64 95 / 0 20 20 10
LGD 59 100 62 96 / 0 0 0 0
GCD 59 104 64 97 / 0 0 0 0
DLS 67 105 75 103 / 0 0 0 10
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...Heat Advisory from 11 AM Wednesday to 11 PM PDT Friday for
ORZ041-044-049-050-502-503-505>508-510-511.
WA...Heat Advisory from 11 AM Wednesday to 11 PM PDT Friday for
WAZ024-026>030-520-521.
&&
SHORT TERM...97
LONG TERM....99
AVIATION...97The national radar mosaic for the moment the first event began.
4 excessive heat. Local standard time, as filed.
Calculated heat risk values at the Dallesport Airport GHCN site recorded temperatures that met or exceeded excessive heat warning criteria on Aug. 17th.
Calculated heat risk values at the Prosser, Richland, Kennewick, and Ice Harbor Dam GHCN sites recorded several days between Aug. 18th and Aug. 22nd of temperatures that met or exceeded excessive heat warning criteria.
Calculated heat risk values at the Yakima GHCN site recorded temperatures that met or exceeded excessive heat warning criteria on Aug. 18th.
Calculated heat risk values at the Ellensburg GHCN site recorded temperatures that met or exceeded excessive heat warning criteria on Aug. 19th.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Washington in 2022Every state in 2022This day in weather historyWarnings in Washington, August 2022
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 1053509, 1053512, 1053513, 1053510.