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U.S. Day 1 Fire Weather Outlook
ZCZC SPCFWDDY1 ALL
FNUS21 KWNS 271556
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1056 AM CDT Thu Aug 27 2026
Valid 271700Z - 281200Z
...CRITICAL FIRE WEATHER AREA FOR FAR NORTHEASTERN
CALIFORNIA...NORTHWESTERN NEVADA...AND SOUTHEASTERN OREGON...
No changes were made to the existing drawn fire weather risk areas
for today. Satellite imagery and GLM data shows thunderstorm
development already underway across portions of western MT.
Precipitation already received in the last 24 hours and resultant
ERCs below the 90th percentile, especially where the latest forecast
guidance shows convection to be most widespread today, has precluded
the introduction of any additional dry thunderstorm area(s) of
concern. Meanwhile, much of the drawn wind/RH areas show transient
scattered cloud cover this morning. Even so, enough solar radiation
is still expected to mix down stronger winds from aloft, aiding the
tightening surface pressure gradient in place across highlighted
areas of the Pacific Northwest. The area of Critical concern, near
the low elevations of southeastern OR, remains on track with
sustained southwesterly winds of 15-25 mph amid RHs of 10-15%
through several hours this afternoon ahead of an advancing cold
front. The front will move across central OR and WA today and
approach the Critical wind/RH area between sunset and midnight
tonight as it slows, turning winds west-northwesterly as it passes.
..Stearns.. 08/27/2026
.PREV DISCUSSION... /ISSUED 0103 AM CDT Thu Aug 27 2026/
...Synopsis...
An upper-level trough will continue to promote fire weather concerns
across portions of the northwestern CONUS, northern Great Basin and
northern Rockies today. Enhanced southwest winds and dry conditions
will bring elevated fire weather conditions across the Columbia
Basin with a more pronounced critical fire weather threat from far
northeastern CA into southeastern OR. Farther east, sufficient
mid-level moisture, upper diffluence ahead of the aforementioned
trough and daytime instability, will aid in development in
high-based thunderstorms across portions of the northern Rockies and
adjacent MT high plains. Breezy offshore winds across Southern
California will present an elevated fire weather threat this evening
and tonight after well-above normal temperatures this afternoon.
...Pacific Northwest into Oregon High Desert and northeastern
California...
Dry, downslope flow into the Columbia Basin is expected today as
upper trough pushes farther into the Pacific Northwest. As the
onshore pressure gradient tightens, west to southwest winds of
around 15 mph (locally 20 mph in areas just east and adjacent to the
Cascades) will develop and couple with RH as low as 15% by
mid-afternoon. These atmospheric conditions along with receptive
fuels will promote an elevated fire weather threat across the
Columbia Basin. Farther south, a 50-60 knot mid-level jet will
stretch from northeastern CA into central ID. Diminishing cloud
cover from southwest to northeast will enhance boundary layer mixing
most across far northeastern CA, far northwestern NV and
southeastern OR where sustained surface winds of 15-25 mph are
expected this afternoon. Within this corridor of stronger winds, RH
should fall to below 10% at times by peak heating. Fuels remain
quite dry with forecast ERCs near the 95th percentile. This
meteorological setup along with a receptive fuelscape (as evidenced
by recent fire activity) supports critical fire weather highlights
from far northeastern CA into southeastern OR.
...Northern Rockies...
A supportive thunderstorm environment will exist over portions of
the northern Rockies as the Pacific Northwest trough translates
eastward. Forcing for ascent ahead of the trough, aligning with
mid/upper level moisture and daytime instability, will bring mainly
high-based thunderstorms to portions of central ID into much of
western MT. Increasing thunderstorm motions to the east-northeast
will be bolstered by strengthening vertical wind shear as the upper
trough pushes east, further limiting rainfall accumulation in lower
elevations. Isolated dry thunderstorm highlights remain over this
region with only minor changes.
...Southern California...
A northerly wind component will increase again this evening and
tonight across portions of southern CA as the offshore pressure
gradient tightens. Hot and dry conditions during the day with near
record high temperatures in the 90s and 100s away from the coast are
supporting increasingly dry fuels across the region. Wind speeds of
10-20 mph with higher gusts are possible in wind prone areas and
terrain gap features across LA/Ventura/Santa Barbara counties. These
winds coupled with RH around 20% will present an elevated fire
weather threat.
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U.S. Day 2 Fire Weather Outlook
ZCZC SPCFWDDY2 ALL
FNUS22 KWNS 271942
Day 2 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0242 PM CDT Thu Aug 27 2026
Valid 281200Z - 291200Z
Potential for dry thunderstorms was considered over portions of the
Central Valley of CA and areas to the southwest to include the
coast. Remnants of former tropical storm Iselle will move over much
of central CA, leading to precipitable water values near or even
exceeding 1 inch at times. However, given the dry state of the dead
fuels (evidenced by ERCs exceeding the 90th percentile) combined
with quick-moving storm motions (near 20-30+ kts) results in
forecast guidance suggesting QPF near 1/10 of an inch. This region
will be closely monitored for inclusion in an isolated dry
thunderstorm area with the next outlook issuance. The existing
Elevated wind/RH areas remain on track for Day 2/Friday with only
minor changes based on the latest forecast guidance placement of the
strongest winds.
..Stearns.. 08/27/2026
.PREV DISCUSSION... /ISSUED 0104 AM CDT Thu Aug 27 2026/
...Synopsis...
An upper-level trough in the Pacific Northwest and attendant
enhanced southwest flow will maintain fire weather concerns for
portions of northern CA into southern OR, as well as northwestern MT
ushering in dry and breezy conditions. Farther south, offshore flow
will support elevated fire weather conditions across portions of
southern CA. A moisture plume from former tropical storm Iselle will
support increasing cloud cover and probabilities for wetting rains
across portions of the Great Basin late Friday into Friday night,
which should limit impacts from cloud to ground lightning.
...Sacramento Valley/northeastern California and southern Oregon...
Broad southwest flow aloft attributed to the Pacific Northwest
upper-level wave and resultant surface troughing east of the
Cascades will evolve Friday. Farther south, an expanding moisture
plume from the Pacific will begin to infiltrate into central CA and
Great Basin. A corridor of dry and breezy conditions will likely
exist between the upper-level trough and increasing mid/upper cloud
cover, resulting in elevated fire weather concerns from the northern
Sacramento Valley northeastward into southern OR. Southwest winds of
around 15 mph and RH of 10-20% will combine with dry fuels to
support an elevated fire weather threat.
...Northwestern Montana...
Dry, downslope flow aided by a surface trough across eastern MT and
broad southwest flow aloft, will affect mainly the adjacent high
plains region east of the Lewis and Flathead Ranges Friday. West
winds of around 15 mph with higher gusts and RH falling to 15-20%
will promote an elevated fire threat amid dry fuels.
...Southern California...
Well above normal afternoon temperatures in the 90s and 100s across
southern California will be followed by a dry, northerly wind
component as a weak offshore flow pattern continues across the
region. Wind speeds of 10-15 mph will be concentrated in favored
terrain gaps and downslope areas in Santa Barbara, Ventura and LA
counties Friday evening and night accompanied by low relative
humidity over an increasingly dry fuelscape.
U.S. Day 3-8 Fire Weather Outlook
ZCZC SPCFWDD38 ALL
FNUS28 KWNS 272137
Day 3-8 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0437 PM CDT Thu Aug 27 2026
Valid 291200Z - 041200Z
...Synopsis...
Expect a series of mid-level troughs to continue impacting the
Pacific Northwest and neighboring areas of the western CONUS
throughout the Extended Outlook time frame. This will leave the west
CONUS coast and the northwestern quadrant of the CONUS under
periodically strong southwest-westerly flow into early next week.
Embedded disturbances will continue to move through the persistent
troughing and along the northern periphery of the flattening ridge.
The current consensus of long term guidance suggests these
shortwaves will contribute to the breakdown/eastward translation of
the ridge, shunting monsoonal moisture to the south and east. As a
result of the synoptic pattern, fire weather concerns will likely
continue through the forecast period across the portions of the
Northwest and nearby regions. However, low predictability and poor
agreement among ensemble members precludes additional probabilities
beyond Day 6/Tuesday.
...Northwest, Northern Great Basin, and Northern California...
Drier southwest flow aloft associated with perpetual troughing over
the northwest CONUS will promote continued fire weather concerns
into early next week. 40% Critical probabilities have been
maintained with minor adjustments for Day 3/Saturday and Day
5/Monday, and introduced across northeastern California,
northwestern Nevada, and southeastern Oregon on Day 6/Tuesday. West
to southwest winds of 15-20 mph and afternoon relative humidity of
15-20 percent will bring near-daily elevated fire weather concerns
over this region. Well below normal temperatures will moderate the
threat slightly, but conditions will remain conducive to wildfire
spread in the absence of a significant precipitation event.
Increasing potential for accumulating rainfall is introduced
mid-next-week over western WA, but forecast uncertainty remains
high.
..Stearns.. 08/27/2026
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