The Horse Prairie wildfire started around 3:30 PM on 08/26/17. |As of 03:30 on 09/01/17, the fire covered 11500 acres and was 15 percent contained.
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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 MFR wrote it up.
The Horse Prairie wildfire started around 3:30 PM on 08/26/17. The cause was unknown.|As of 03:30 on 09/01/17, the fire covered 11500 acres and was 15 percent contained. 2.7 million dollars had been spent on firefighting efforts.
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 Medford, OR wrote its last area forecast discussion before the first event at Aug 26, 2:21 PM PST, 9 minutes earlier.
Area Forecast Discussion
National Weather Service Medford OR
321 PM PDT Sat Aug 26 2017
Updated Fire Weather Section
.SHORT TERM...A strengthening upper ridge over the region combined
with a surface thermal trough will bring a hot and dry pattern to
the area through Monday. The thermal trough will have diurnal
fluctuations and shift inland in the afternoons today and Sunday.
Then the thermal trough will shift inland on Monday as a trough
approaches the Pacific Northwest. Beginning Monday, southerly
moisture will move up into southeast portions of the area and
combine with instability to bring a slight chance for
thunderstorms to portions of Lake and eastern Modoc counties.
Through Monday, expect warming temperatures as the upper level
ridge strengthens over the region. Numerous active fires in
southwest Oregon and northwest California will continue to bring
areas of smoke. The smoke will keep temperatures lower than they
would be if the skies were clear, especially in areas west of the
Cascades in Oregon and in portions of western Siskiyou county.
Temperatures are still expected to rise on Sunday into the 90s
across inland valleys and near 100 in some western valleys,
including in portions of the Rogue and Shasta valleys. Similar
conditions are expected on Monday. Hot and dry conditions with
some local areas of breezy or gusty winds will result critical
fire weather conditions for the next couple days. Red flag
warnings are in effect for portions of the Cascades west through
Monday. Please see the RFWMFR for details.
Additionally, smoke will continue to be a problem with air
quality impacts for many areas in southwest Oregon and northwest
California. Expect only fluctuations in smoke levels through early
Monday. Then as the thermal trough moves inland Monday afternoon,
we may see an improvement in air quality for some areas,
especially in Coos and Douglas counties, as west winds develop
during the afternoon. An air quality alert is in effect for
portions of Curry, Douglas and Klamath counties as well as
Josephine and Jackson counties. Please see the AQAMFR for details.
The flow shifts to south to southwest as the upper trough moves
near the coast Tuesday. This may allow some areas to see
improvement while others will remain impacted by smoke due to
continued fires in southwest Oregon and northwest California.
Expect a return to a high pressure ridge and surface thermal
trough later in the week by Thursday. This may result in similar
area of smoke as seen over the last couple days.
Models are indicating mid level moisture moving up from the south
and into Lake and Modoc counties beginning Sunday and continuing
through Wednesday. Conditions are only marginally stable on
Sunday and expect some cumulus development but do not expect any
thunderstorms Sunday afternoon and evening. Monday and Tuesday,
there is a slight risk for thunderstorms over portions of Lake and
eastern Modoc counties where there is weak instability and CAPE
and where weak upper level disturbances may move into the area.
Storm development looks more favorable for areas east of the CWA
though on these days. On Wednesday, as an upper trough moves
into the coast, lingering moisture and instability will bring a
slight chance of thunderstorms again to eastern portions of Lake
and Modoc counties. Also during this period with an approaching
trough, southwest winds will become breezy to gusty over northern
California and east of the Cascades with strongest winds expected
Tuesday afternoon and evening. Otherwise, this trough will bring
slightly cooler temperatures Tuesday into Wednesday.
.LONG TERM...Thursday through Saturday...There is a return to
high pressure with an upper level ridge building again over the
region Thursday through next Saturday. This will bring a return
to hot and dry conditions with temperatures warming into the 90s
to near 100 over inland valleys. A surface thermal trough will
bring light to moderate offshore easterly flow during the
nighttime and morning hours from the Cascades west, with winds
changing to north to northwest during the afternoon. Of note,
this is a similar pattern as seen over the last couple days and
there may be increased areas of smoke with active fires over
southwest Oregon and northwest California Thursday through
Saturday.
&&
.AVIATION...26/18 TAF CYCLE...Along the coast...the smoke from the
Chetco Bar fire will also occasionally reduce visibility to MVFR/IFR
in and around Brookings. Otherwise, VFR is expected through the day
before fog comes back to the coast tonight.
Almost all inland areas will have to deal with reduced visibility
(MVFR and occasional IFR) due to wildfire smoke through the TAF
period with the thickest smoke in western Siskiyou County valleys,
the Applegate Valley and near the High Cascades/Umpqua North
complexes, where visibility could be reduced to just a few hundred
feet at times. -Schaaf/Petrucelli
&&
.MARINE...Updated 245 AM PDT Saturday 26 August 2017...
The thermal trough will move inland today as high pressure centered
offshore strengthens. Small craft advisory level conditions will
linger today as moderate gusty winds and fresh swell gradually
diminish. Sunday through Wednesday winds and seas will remain
relatively light as the high over the Pacific continues to influence
surface conditions. The thermal trough is likely to rebuild later
next week resulting in another round of northerlies and more
hazardous seas. BTL
&&
.FIRE WEATHER...Updated 330 PM PDT Saturday, 26 August 2017...
...AN EXTENDED PERIOD OF ACTIVE BURNING CONDITIONS IS EXPECTED
THROUGH INTO EARLY NEXT WEEK...
A building upper level ridge over the area will cause hot, dry
weather into early next week. A surface thermal trough will meander
near the coast, then shift inland Sunday and Monday. Increasing
instability will lead to Haines 5 and 6 conditions through Monday,
with peak dryness and instability expected on Sunday. This will lead
to a moderate to high probability of plume dominated fire growth on
new and uncontained fires. Locally gusty south winds in the Shasta
Valley will bring very low relative humidities this evening and
again Sunday afternoon and evening. For these reasons, we have
upgraded all Fire Weather watches to Red Flag warnings. Please refer
to RFWMFR for specific details.
The threat of lightning is low across the area through mid next
week, but model guidance still shows there is a very slight chance
of thunderstorms over far eastern sections each afternoon Monday to
Wednesday.
It should be noted that the very dry conditions in place with
increasing dryness continue to result in concerns for cumulative
effects of ongoing hot, dry weather across the area. Please keep
this in mind as you engage wildfires this week, as peak fire season
continues. Without the mitigating effects of smoke, we'd be looking
at daily high temperature records this week. BTL/MAS
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...Red Flag Warning from 1 PM to 9 PM PDT Sunday for ORZ618-619.
Red Flag Warning from 1 PM to 9 PM PDT Monday for ORZ619.
Red Flag Warning from 1 PM to 9 PM PDT Sunday for ORZ617-623.
CA...Red Flag Warning until 9 PM PDT this evening for CAZ281.
Pacific Coastal Waters...Small Craft Advisory until 5 AM PDT Sunday
for PZZ370-376.
Small Craft Advisory for hazardous seas until 8 PM PDT this
evening for PZZ350-356-370.
CC/MASThe national radar mosaic for the moment the first event began.
1 wildfire. Local standard time, as filed.
The Horse Prairie wildfire started around 3:30 PM on 08/26/17. The cause was unknown.|As of 03:30 on 09/01/17, the fire covered 11500 acres and was 15 percent contained. 2.7 million dollars had been spent on firefighting efforts.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Oregon in 2017Every state in 2017This day in weather historyWarnings in Oregon, August 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: 710871.