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; 7 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 15, 9:30 PM PST, 2 hours 30 minutes earlier.
Area Forecast Discussion
National Weather Service Pendleton OR
1030 PM PDT Mon Aug 15 2022
updated the aviation discussion
.EVENING UPDATE... The previous forecast is on track this
evening with little to no changes needed; minor updates were made
based off the latest guidance. Hot temperatures remain the focus
moving forward as a ridge of high pressure builds overhead Tuesday
into the middle of the week. Expect well above normal high
temperatures come Wednesday and Thursday with triple digits across
the Columbia Basin and other low elevation areas. As a result, a
heat advisory remains in effect much of the region starting on
Wednesday. Thunderstorms, particularly over Central Oregon, may also
be a noteworthy concern starting on Wednesday as well. However,
there is still some uncertainty as to the placement, coverage, and
timing of convective activity later in the week with models
depicting less of a signal for mountain T-storms Friday into the
weekend.
&&
.PREV DISCUSSION... /issued 410 PM PDT Mon Aug 15 2022/
SHORT TERM...Tonight through Wednesday night...An upper ridge is
currently building into the PacNW, with a warming trend taking
place. Conditions are dry and stable today, which is expected to
continue on Tuesday. With most of the forecast area being west of
the ridge axis, the flow aloft will be south to southwest. This
will eventually pull monsoonal moisture and instability from the
south into the region. This will also help to cause temperatures
to warm back into the triple digit heat readings. As such, a Heat
Advisory has been issued for most of the forecast area from 11 AM
Wednesday through at least 11 PM Friday evening. The hottest day
looks to be Wednesday, with a degree or two of cooling early in
the extended period (Thursday and Friday). Maximum temperatures
are expected to be in the 100-105 range across the lower
elevations, and 80s to mid 90s in mountainous areas. The EFI
index is showing anomalies of temperatures being hotter than
normal with EFI index values of .8 to .9 over portions of the CWA
on Wednesday afternoon, continuing into the extended forecast
period.
The other concern for the short term period, through Wednesday
night, is the potential for mostly dry thunderstorms over central
OR Wednesday afternoon and evening. These thunderstorms will be
confined to central OR on Wednesday. The last couple of model runs
have backed off on the threat and areal coverage of thunderstorms,
therefore forecast confidence has decreased enough to not issue
any fire weather highlights at this point (mainly for
thunderstorms with abundant lightning). The Deterministic and
ensembles are in good agreement through Day 3, looking at the
cluster analysis. This is especially true for the ECMWF, which
has the least amount of variance for both phase space and EOF
fields.
Winds are expected to be light and mainly terrain driven in the
late night and morning hours, and then dominated by the general
winds in the afternoon and evenings. The greatest chance for
breezy winds will be through the Cascade gaps, passes as well as
the eastern Columbia Gorge and north central OR. If the winds in
these areas increase more, it could pose a Wind/RH fire weather
threat. At this time, and not expecting that, as least through
Wednesday night. 88
LONG TERM...Thursday through Monday...The main concerns in the
extended will be hot late-summer weather with a slight chance of
thunderstorms for the mountains. Shorter days and longer nights are
beginning to have a noticeable effect on temperatures so while it
will be hot (generally 95-105), very hot temperatures will be harder
to achieve and overnight lows will be somewhat cooler in the mid 50s
to upper 60s for our population centers. Regardless, confidence is
high in advisory level heat through Friday, with lower confidence
for highlights extending through Sunday.
Ensemble mean 500 mb heights and vorticity depict an upper-level
ridge as the dominant longwave feature through Sunday, with a
shortwave riding around the ridge and across the Pacific Northwest
on Thursday and another, potentially stronger, shortwave impacting
northern Washington and British Columbia on Friday. Ensemble means
advertise a more substantial trough passage Monday, though the EPS,
GEFS, and CMC all differ in amplitude and timing. Notably, the
troughing signal in the 12Z GEFS' is trending weaker while the 12Z
EPS' signal is trending stronger. Moreover, confidence in the
pattern for Saturday onward is more low/moderate than high.
On Thursday, some modest monsoonal moisture transport into central
Oregon combined with modest instability and weak synoptic support
from an approaching shortwave should allow a slight chance of
thunderstorms across the central Oregon Cascades and perhaps further
east into the Ochocos and surrounding mountains. Confidence is lower
in thunderstorm chances for the Washington Cascades Thursday
afternoon, but have bumped up PoPs over what the NBM is forecasting
due to some elevated instability along the Cascade crest and
Wenatchee Mountains.
Ensemble and deterministic guidance both suggest a stronger
shortwave will move onshore into northern Washington and British
Columbia on Friday, but questions about instability, track, and
moisture availability all lead to low confidence in any shower and
thunderstorm development at this time. Temperatures are expected to
cool a few degrees with a push of marine air and locally breezy
conditions through the Cascade gaps, but heat concerns will remain.
Saturday through Monday, uncertainty in the pattern grows, as
evidenced by a broad range of solutions ranging from a deep cut-off
low to troughing offshore with ridging over the Inland Northwest.
Should the cut-off low solution develop, cooler temperatures and
precipitation chances will return. The ridging pattern would lead to
continued heat concerns through at least Sunday. Plunkett/86
&&
.AVIATION...vfr conditions will continue at all taf sites for the
next 24 hours. Meanwhile mostly clear skies along with winds between
5 to 20 mph will continue through the period.
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 60 96 62 102 / 0 0 0 0
ALW 63 99 65 104 / 0 0 0 0
PSC 64 99 65 104 / 0 0 0 0
YKM 60 97 60 102 / 0 0 0 0
HRI 61 100 63 105 / 0 0 0 0
ELN 60 97 60 102 / 0 0 0 0
RDM 52 94 57 98 / 0 0 0 10
LGD 56 96 60 100 / 0 0 0 0
GCD 57 100 61 102 / 0 0 0 0
DLS 64 99 68 104 / 0 0 0 0
&&
.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.
&&
UPDATE...99
SHORT TERM...88
LONG TERM....86
AVIATION...97The national radar mosaic for the moment the first event began.
7 excessive heat. Local standard time, as filed.
The Eden RAWS recorded consecutive maximum daily high temperatures of 95 degrees or greater from Aug. 16th through the 18th.
Calculated heat risk values at the Dallesport Airport GHCN site recorded temperatures that met or exceeded excessive heat warning criteria on the 17th.
Calculated heat risk values at the Moro GHCN site recorded consecutive days between Aug. 17th and 18th of temperatures that met or exceeded excessive heat warning criteria.
The Roberts Butte RAWS and the Joseph Airport AWOS recorded consecutive maximum daily high temperatures of 95 degrees or greater between Aug. 17th and 18th.
Calculated heat risk values at the Pendleton Airport and Pilot Rock GHCN sites recorded temperatures that met or exceeded excessive heat warning criteria on Aug. 18th.
Calculated heat risk values at the La Grande GHCN site recorded consecutive days between Aug. 18th and 19th of temperatures that met or exceeded excessive heat warning criteria.
Calculated heat risk values at the Boardman GHCN site recorded consecutive days between Aug. 21st and 22nd of temperatures that met or exceeded excessive heat warning criteria.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Oregon in 2022Every state in 2022This day in weather historyWarnings in Oregon, 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: 1053504, 1053497, 1053503, 1053506, 1053498, 1053500, 1053502.