Washington, 2021

Excessive Heat in Washington, June 26 to 29, 2021

June 26 to 29, 2021 · NWS PQR · 5 events in 5 counties and zones

A high pressure heat dome over the region led to stretch of extreme heat, shattering records from June 26 through June 29. Hot temperatures resulted in many people seeking locations to cool off in local rivers and beaches, which led to one drowning, as well as multiple people going to local hospitals for treatment of typical heat-related medical symptoms, including one reported death.

The toll

Deaths
5
Injuries
0
Property damage
None recorded
Crop damage
None recorded
Events
5

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.

What happened

The episode as NWS PQR wrote it up.

A high pressure heat dome over the region led to stretch of extreme heat, shattering records from June 26 through June 29. Hot temperatures resulted in many people seeking locations to cool off in local rivers and beaches, which led to one drowning, as well as multiple people going to local hospitals for treatment of typical heat-related medical symptoms, including one reported death.

What forecasters said that day

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 Portland, OR wrote its last area forecast discussion before the first event at Jun 26, 8:07 AM PST, 1 hour 53 minutes earlier.

Area forecast discussion, Jun 26, 8:07 AM PST, 1 hour 53 minutes before
Area Forecast Discussion...UPDATED
National Weather Service Portland OR
907 AM PDT Sat Jun 26 2021

Updated aviation discussion

...UNPRECEDENTED HEAT WAVE EXPECTED THIS WEEKEND INTO EARLY NEXT
WEEK, FOLLOWED BY GRADUAL COOLING...

.SYNOPSIS...An anomalously strong high pressure system aloft is
beginning to build into the Pacific Northwest and will continue to do
so this weekend, bringing a stretch of unusually hot weather to the
region. The resulting heat is likely to break numerous high
temperature records, with some all-time heat records in serious
jeopardy. Coastal areas will be cooler, especially along the beaches.
The hottest day overall appears to be Sunday, with only minimal
cooling expected Monday, but coastal valleys and perhaps
the Eugene/Corvallis area should see more cooling. The most extreme
heat is expected to wane somewhat next week, but inland temperatures
are still expected to remain well above seasonal normals.

&&

.SHORT TERM...Today through Monday...Perhaps the most intense
heatwave for our region since the late 19th century - or at
least close to it - is beginning to take shape across the Pacific
Northwest as anomalously strong high pressure builds aloft. The next
couple of days will be record breakers as dangerously hot
temperatures grip much of the region. Coastal beaches will likely be
the only outdoor area to escape the heat.  In addition daily and June
high temperature records shattered, will likely see all-time records
broken too through the weekend.

Today will be 7 to 10 deg over Friday's highs, and Sunday is still
looking to be the hottest day.	Model consensus has trended higher so
have nudged temperatures inland up a couple of degrees to keep
forecast close to the mean of the NBM and is close to the ECMWF as
well.  As an example of how hot the air mass is and forecast to be,
the 850 mb temperature Friday afternoon was measured at 19.4C from
the Salem sounding. The forecast for this afternoon is around 25C
and 29-31C for Sunday afternoon. In addition to the hot air mass,
offshore flow develops Sunday through the Columbia Gorge which could
potentially maximize the potential heat at the surface given the air
mass aloft as the wind warm in the downslope flow off the Cascades.

There will be cooling for Monday but how much is a bit of a
challenge. There is an upper level and surface low projected to
approach the region from the southwest Sunday night and Monday, this
will induce a southwest onshore flow as the surface ridge builds on
the coast.  This will bring a deeper marine layer that should spill
into the southern Willamette Valley, but there more uncertainty if it
will make to the north Willamette Valley to provide much needed
relief. Temperatures still look to be in the upper 90s in the south
valley to around 105-108 range Salem northward.

After nearing monthly heat records on Saturday and possibly all-time
heat records on Sunday, temperatures will struggle to fall below 70
degrees in many areas at night. Downtown and inner eastside Portland
will be slowest to cool each night, given their urban heat island
effect. It is fathomable that some of these neighborhoods will fail
to fall below 80 degrees for a 60 to 72-hour period between Saturday
morning and Monday night. Unprecedented warm nights will offer little
relief from the daytime heat, compounding the danger of heat-related
illness for those without access to air conditioning. Areas outside
of city centers will be relatively cooler, but even the cooler
outlying areas will see lows mainly in the 60s and lower 70s Saturday
night and again Sunday night. Even the mountains will be very warm at
night, with areas along and above thermal belts stuck in the 70s or
perhaps even lower to mid 80s for lows.

In essence, the immediate coast will be the only outdoor place where
people can truly escape the heat the next few days. Those stuck in
inland areas without access to air conditioning are in real danger of
heat-related illness, especially in Downtown Portland and the inner
eastside of Portland. People in these areas should determine where
cooling shelters are available in their area, or will likely need to
be creative about finding ways to keep cool during this unprecedented
heat wave.

No changes to the existing Excessive Heat Warning. A Fire Weather
Watch has been issued for the western slopes of the Washington
Cascades, as well as the North Oregon Cascades and foothills, due to
the easterly breezes expected there late Sat night through Mon
morning.  /mh Weagle

.LONG TERM...Tuesday through Friday...The long term forecast looks to
be disappointing for anyone inland who is looking for substantive
relief from the heat. The southwesterly marine push expected to cool
off the coastal valleys Monday will likely become more prolific
Monday night and Tuesday as 500 mb heights fall a bit, mainly due to
an upper low lifting north across our offshore waters. This may even
allow some low clouds into the coastal valleys Mon night and perhaps
Tue night, along with more widespread "cooling" inland. The result
will be much more pleasant temps for the coastal valleys Tue/Wed,
while the inland valleys fall into the upper 80s to mid 90s for highs
- still a good 10 to 20 degrees above late June/early July normals.
Will need to watch the above-mentioned upper low closely, as any
closer of an approach could bring the chance of isolated
thunderstorms Mon/Tue. With the 12z ECMWF ensembles showing little
chance of 500 mb heights lowering below the upper 5800 meter range
for the remainder of the week, the marine layer will likely remain
very shallow and thus temperatures will remain several degrees above
normal for the foreseeable future.  Weagle

&&

.AVIATION...Strong high pressure and a sinking air mass will
maintain clear skies across the region through at least 18Z
Sunday. Only significant flight category concern is from low
marine stratus along the immediate central coast, mainly from
KTMK southward where LIFR cigs and visibilities will most likely
return between 03-06Z Sunday. Very shallow radiational fog
is also possible at KAST around and shortly after sunrise.

While it's outside of our normal scope of forecasting, want to
continue bringing attention to expected density altitude
limitations for area pilots. The extreme temperatures over the
next few days will bring density altitudes a few thousand feet
higher than this area typically experiences, even during the
normal hottest parts of summer.

For detailed regional Pac NW aviation weather information, go
online to: https://weather.gov/zse

KPDX AND APPROACHES...VFR with no concerns through 18Z Sunday.
-TK/JBonk

&&

.MARINE...Northerly flow will continue over the waters through
at least Sunday afternoon. Low pressure will develop over the
coastal waters Sunday night resulting in nearshore winds backing
southerly first followed by the outer waters as the low center
slowly drifts westward through Monday evening. Am most uncertain
regarding the strength of these southerly winds as a slight
majority of the weather models, including most of the high
resolution versions, are now showing gusts at 21 kts or below.
The slim minority of models continue to show gusts 20-25 kts with
the strongest 25-30 kts on Monday. Have adjusted the forecast to
favor the weak majority and am keeping gusts around 20 kts. It's
still largely a coin flip, however. The aforementioned low moves
away from the waters Tuesday and high pressure returns Wednesday
as winds veer back to northerly. Seas generally stay 4-7 feet,
becoming most steep under the southerly wind waves pushing
against the northerly currents. /JBonk

&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...Excessive Heat Warning until 11 PM PDT Monday for Cascade
     Foothills in Lane County-Cascades in Lane County-Central
     Coast Range of Western Oregon-Central Columbia River Gorge-
     Central Willamette Valley-Coast Range of Northwest Oregon-
     Greater Portland Metro Area-Lower Columbia-Northern Oregon
     Cascade Foothills-Northern Oregon Cascades-South
     Willamette Valley-Upper Hood River Valley-Western Columbia
     River Gorge.

     Fire Weather Watch from late tonight through Monday morning for
     Mt. Hood National Forest West of Cascade Crest-North
     Oregon Cascade Foothills.

     Excessive Heat Warning from 11 AM to 9 PM PDT Sunday for North
     Oregon Coast.

WA...Excessive Heat Warning until 11 PM PDT Monday for Central
     Columbia River Gorge-Greater Vancouver Area-I-5 Corridor
     in Cowlitz County-South Washington Cascade Foothills-South
     Washington Cascades-Western Columbia River Gorge-Willapa
     Hills.

     Fire Weather Watch from late tonight through Monday morning for
     Extreme South Washington Cascades and Foothills.

     Excessive Heat Warning from 11 AM to 9 PM PDT Sunday for South
     Washington Coast.

PZ...None.
&&

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Event by event

5 excessive heat. Local standard time, as filed.

Excessive Heat, Central Columbia River Gorge

When
June 26, 10:00 AM PST to June 28, 8:00 PM PST
Where
Central Columbia River Gorge forecast zone
Reported by
Mesonet

Very hot temperatures. A Mesonet Weather Station near Underwood observed three consecutive days with temperatures above 105 degrees. This station reported a maximum temperature of 107 on June 26, 113 on June 27, and 115 on June 28. The minimum temperatures were in the lower 70s on June 27 and June 28.

Excessive Heat, Western Columbia Gorge

When
June 26, 10:00 AM PST to June 28, 8:00 PM PST
Where
Western Columbia Gorge forecast zone
Reported by
Trained Spotter

Very hot temperatures. There were three consecutive days with maximum temperatures above 100 degrees. Maximum temperatures peaked around 108 degrees on June 27, and 112 degrees on June 28. The minimum temperatures were in the mid 70s on June 27 and June 28.

Excessive Heat, Greater Vancouver Area

When
June 26, 12:00 PM PST to June 29, 6:00 PM PST
Where
Greater Vancouver Area forecast zone
Deaths
3 direct, 0 indirect
Reported by
ASOS

Record breaking temperatures for 3 days in a row. Vancouver (KVUO) recorded high temperatures of 108, 112, and 115 F. Three heat related deaths were reported in Clark County.

Excessive Heat, Lower Columbia

When
June 26, 12:00 PM PST to June 29, 6:00 PM PST
Where
Lower Columbia forecast zone
Deaths
1 direct, 0 indirect
Reported by
Broadcast Media

Very hot temperatures. There were three consecutive days with maximum temperatures greater than 100 degrees. Maximum temperatures were around 108 degrees on June 27 and June 28. There was one death reported due to heat related illness.

Excessive Heat, South Coast

When
June 26, 12:00 PM PST to June 28, 6:00 PM PST
Where
South Coast forecast zone
Deaths
0 direct, 1 indirect
Reported by
Trained Spotter

A reliable SkyWarn spotter (Pacific-34) called to report his temperature sensor was recording 105 degrees. A middle-aged man drowned on Sunday, June 27.

The people who died

As the offices recorded each death: direct deaths were caused by the weather itself, indirect ones by something it set in motion.

EventDateAgeSexWhereKind
Excessive Heat, Greater Vancouver Area2021-07-09MaleUnknownDirect
Excessive Heat, Greater Vancouver Area2021-07-01UnknownDirect
Excessive Heat, Greater Vancouver Area2021-06-28UnknownDirect
Excessive Heat, Lower Columbia2021-06-2764MaleOtherDirect
Excessive Heat, South Coast2021-06-2744MaleIn WaterIndirect

What these are

Excessive Heat
Heat at or above the local excessive heat warning criteria, or heat that caused deaths.

After NWS Directive 10-1605, the rules offices file Storm Data by.

The same day elsewhere

More

Every storm in Washington in 2021Every state in 2021This day in weather historyWarnings in Washington, June 2021

Sources

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: 970001, 970002, 965817, 965818, 965819.