878
FNUS28 KWNS 172202
FWDD38

Day 3-8 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0500 PM CDT Mon Aug 17 2026

Valid 191200Z - 251200Z

...Synopsis...
A ridge continues to slowly build over the Great Basin to start the
extended forecast period. The pressure gradient will tighten on Day
4/Thursday as a trough approaches the west CONUS coast. A mid-level
low pressure system will near the Pacific Northwest coast on Day
5/Friday as the upper-level jet max peaks over northern CA and
southern OR. This will provide synoptic lift to portions of
north-central OR and then much of central WA under the left exit
region of the jet streak on the afternoon of Day 5/Friday. The
trough will begin to lift northeastward as it becomes slightly
negatively-tilted progressing into Day 6/Saturday. High pressure
remains in place over much of the southwestern half of the CONUS
with shortwave trough passages periodically moving across the crest
of the high through the northern states. While slight differences in
timing of the aforementioned trough exist, the overall pattern
evolution remains similar amongst various ensemble forecast
guidance.

...Pacific Northwest/Northern California/Great Basin...
The Pacific Northwest and immediately neighboring areas of northern
California and the Great Basin will remain foci through much of the
extended forecast. Starting on Day 4/Thursday and continuing through
Day 6/Saturday, expect multiple consecutive days of gusty
southwesterly winds combined with warm and dry weather as the
aforementioned large trough approaches from the west. Near-normal
conditions in the short-term followed by increasing above-normal
temperatures Day 3/Wednesday through Day 5/Friday will culminate in
a cold front passage on Day 6/Saturday as the trough approaches.
Given the jet aloft and surface conditions that would support deep
daytime mixing, a favorable pattern remains in place for dry and
breezy weather to overlap very dry fuels across northeastern CA,
southern OR, and northwestern NV; thus, 40% Critical probabilities
were maintained on Day 4/Thursday through Day 6/Saturday. Given the
aforementioned upper-level support, limited (but sufficient enough
to support deep instability) moisture, and dry fuels still in place
over much of the area immediately east of the Cascades, an area of
10% Dry Thunderstorm risk was introduced over much of the central
and northeastern Pacific Northwest region on Day 5/Friday, which may
linger through the night in some areas. This dry thunderstorm
potential may reemerge on Day 6/Saturday, particularly across far
northeastern WA, northern ID, and far western MT, but precipitation
received on Day 5/Friday will preclude an additional area for now.

..Stearns.. 08/17/2026

...Please see www.spc.noaa.gov/fire for graphic product...

$$