A wildfire started on the 4th 2 miles SE of Lester in the Central Cascades and burned 848 acres through the middle of the month. No structures were lost.
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 SEW wrote it up.
A wildfire started on the 4th 2 miles SE of Lester in the Central Cascades and burned 848 acres through the middle of the month. No structures were lost.
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 Seattle, WA wrote its last area forecast discussion before the first event at Sep 4, 7:54 AM PST, 5 hours 6 minutes earlier.
Area Forecast Discussion
National Weather Service Seattle WA
854 AM PDT Mon Sep 4 2017
.SYNOPSIS...A strong upper level ridge will remain over Western
Washington through Tuesday. A thermally induced trough of low
pressure at lower levels over the interior will shift to the
coastal zones giving low level offshore flow. Record high
temperatures are likely today and tomorrow, and the air mass will
become increasingly smokey from wildfires to the east of the area.
On Wednesday, the ridge and thermal trough will shift eastward
giving a marine push and a cooling trend. A weak upper trough
will bring cooler weather with a chance of showers Thursday and
Friday.
&&
.SHORT TERM...The main message this morning continues to be the
record warm conditions across the region for the next couple of
days, the high fire danger in the mountains, and the increasingly
smokey air mass.
A strong ridge of high pressure aloft sits from west-central
British Columbia southward across the Pacific Northwest this
morning. At the surface, offshore flow is increasing as thermal
troughing strengthens along the Pacific coast as a 1025 to 1030 mb
high bridges from south-central Alberta into central British
Columbia. Short term models continue to show offshore flow
increasing today through Tuesday as the ridge to our northeast
drops down into eastern portions of Washington and Oregon. The
increase in offshore flow combined with warm low to mid level
temperatures means that high temperatures today should easily
reach record levels with lower to mid 90s along the west slopes of
the Cascades and from the Seattle area southward. The west slopes
of the Olympics will also be quite hot today in the increasing
offshore flow with Forks getting into the lower 90s.
Visible satellite imagery this morning shows clear skies across
the area with smoke over the Cascades. Stampede Pass is reporting
a visibility of 1.25 miles and a thicker smoke base of 5000-6000
ft MSL. The smoke is now seen to be shifting westward into the
lowlands. Experimental high-resolution smoke dispersion models
all forecast smoke to push westward today and become rather thick
across the area tonight into Tuesday. The smoke will likely
influence the temperatures, keeping low temperatures warm,
preventing good relative humidity recovery, holding temperatures
down several degrees on Tuesday, and provide a 24 hour or so
period of poor air quality. The current high temperature
forecasts are on the lower third of the guidance envelope, which
seems good. Highs will still be in record territory despite the
smoke. A heat advisory is in effect for much of the area through
Tuesday.
A shallow marine push will begin late Tuesday afternoon and
increase later Wednesday. The shallow marine air will provide
significant cooling to the coastal zones and 5-8 degrees cooling
in the interior on Wednesday. By later Wednesday, the remnants of
Tropical Storm Lidia, embedded in the southerly flow aloft, will
arrive and give a slight chance of thunderstorms to mainly the
western half of the forecast area.
Current forecasts are in good shape. The only change this morning
was to increase fog coverage for the coast, the Chehalis Gap area,
and portions of the south interior for Tuesday night and
Wednesday. Albrecht
.LONG TERM...From the previous long term discussion: Extended
models in good agreement on Thursday with an upper level trough
approaching the Coast and showers out ahead of the trough moving
into the area during the day. Low level onshore flow continuing
with the marine layer over the interior deepening. This will cool
high temperatures for the interior back down into the upper 60s to
mid 70s, normal for this time of year.
Upper level trough moving through the area on Friday keeping a
chance of showers in the forecast for Thursday night and Friday.
Differences in the model solutions start showing up for next
weekend with the ECMWF a little stronger with the flat upper level
ridge over the area versus the GFS. Weak system moving by to the
north on Saturday with the strong ridge ECMWF solution fairly dry
while the weaker ridge GFS solution allows some light
precipitation to move through the area. The GFS stalls the front
over the area Saturday night into Sunday while the stronger ECMWF
keep the precipitation to the north. Will stay with the broad
brush chance of showers forecast for the weekend, High
temperatures will stay near normal, in the mid 60s to mid 70s.
Felton
&&
.AVIATION...A strong upper ridge and low level thermal low pressure
will remain over the area through Tuesday. The air mass is
dry with southwest flow aloft and low level northerly to
easterly flow. Smoke is expected to spread into the area from the
east today--it will be elevated/aloft initially but
overnight tonight the smoke should settle down to the surface and
bring reduced visibilities. Tuesday will be a rather warm smoky day.
KSEA...Mostly clear this morning. Elevated smoke will likely
reach the Seattle area this afternoon and the vsby should drop
tonight as the smoke settles down to the surface. NNE breeze.
&&
.MARINE...The thermal trough is along the coast this morning and
winds are light and variable, but there should still be a pretty
good northerly breeze to about 15kts this afternoon for most of the
waters. Winds in the Strait will be easterly through Tuesday except
perhaps coming around to a light westerly for a few hours this
evening. Onshore flow will develop Tuesday evening as the thermal
trough moves inland. A weak front will move through the area
Thursday night and Friday.
&&
.CLIMATE...From the previous Climate Discussion: Since records
started in the 1890s in Seattle there has never been more than 2
days in a row with highs in the 90s in September. There has also
never been an entire month of September with more than 2 days in
the 90s. With a high of 90 the last couple of days Seattle has a
good chance of recording 4 consecutive days in the 90s for the
first time ever in September as well as breaking the record for
most days in the 90s in September. There has already been 7 days
in the 90s in August and September. The most for the two months
combined on record. The previous record was 6 days set in multiple
years with the last occurrence in 2016. Felton
&&
.FIRE WEATHER...Offshore wind flow will lead to critical fire
weather today and Tuesday for a couple of reasons.
First, the 850-700 mb layer will be critically dry and unstable
through Tuesday, leading to Mid-Level Haines 6. This setup mainly
affects fires above about 1500-2000 feet elevation. Under such
conditions, fires in the Cascades and Olympics can experience
significant growth.
The offshore flow will also cause low humidity and moderate
breezes in a few places. The Ellis Mtn RAWS site on the northwest
Olympic Peninsula observed critical combinations of east wind and
low RH last night, and this will continue at times over the
northwest peninsula until mid-day Tuesday. Over the Cascades from
the Glacier Peak area southward, east wind will strengthen through
Tuesday morning, leading to critical combinations of wind and low
RH there. Looks like Tuesday morning will be the most favored
time in the Cascades.
East wind will also bring a lot of smoke from east of the Cascade
crest into Western Washington on Tuesday.
Onshore flow will develop on Wednesday, ending the two days of
critical fire weather for Western Washington. There is a marginal
setup for a little lightning on Wednesday night. Haner
&&
.SEW WATCHES/WARNINGS/ADVISORIES...
WA...Heat Advisory from noon today to 10 PM PDT Tuesday for Bellevue
and Vicinity-Bremerton and Vicinity-East Puget Sound
Lowlands-Hood Canal Area-Lower Chehalis Valley Area-Seattle
and Vicinity-Southwest Interior-Tacoma Area.
Red Flag Warning from noon today to 8 PM PDT Tuesday for West
Slopes of the Central Cascades Generally above 1500 Feet-
West Slopes of the North Cascades Generally above 1500 Feet.
Red Flag Warning until 8 PM PDT Tuesday for East Portion of the
Olympic Mountains-West Portion of the Olympic Mountains.
Red Flag Warning until 1 PM PDT Tuesday for North Coastal
Lowlands.
PZ...None.
&&
www.weather.gov/seattle
You can see an illustrated version of this discussion at
www.wrh.noaa.gov/sew/gafd/latest_webafd.html1 wildfire. Local standard time, as filed.
A wildfire started on the 4th 2 miles SE of Lester in the Central Cascades and burned 848 acres through the middle of the month. No structures were lost. It cost $4.5 million dollars to suppress this fire.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Washington in 2017Every state in 2017This day in weather historyWarnings in Washington, September 2017
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: 718096.