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U.S. & Canada 00-UTC 48 Hour Surface Smoke Forecast
Map is in operation from early April through October 31
U.S. Day 1 Fire Weather Outlook
ZCZC SPCFWDDY1 ALL
FNUS21 KWNS 101634
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1134 AM CDT Sat Oct 10 2026
Valid 101700Z - 111200Z
...Sierra Front into central/northern Nevada...
Accelerating southwesterly deep-layer flow is expected across the
Great Basin through today as a mid/upper trough deepens across the
Northwest. Latest model guidance consensus shows a marked delay in
the onset of cloud cover and deeper atmospheric moisture streaming
northeastward from Tropical Storm Rachel into southern NV. A
resulting corridor of sustained southwesterly 20-25 mph winds
accompanying a dry and well mixed boundary layer will contribute to
minimum daytime RH as low as 10% across the Basin and Range
landscape of central NV. This critical fire weather environment
should be attenuated somewhat by marginal fuels although the some
degree of wildfire risk will be present after multiple days of above
normal temperatures and dry conditions. Thus, extended Elevated fire
weather highlights into central NV to account for the dry and breezy
conditions expected this afternoon.
..Williams.. 10/10/2026
.PREV DISCUSSION... /ISSUED 0100 AM CDT Sat Oct 10 2026/
...Synopsis...
An amplifying mid/upper trough will migrate slowly southward across
portions of the Northwest, with strong southwesterly flow aloft
extending from the Great Basin into the northern/central Plains. At
the surface, an initially stationary boundary/slow moving cold front
will extend from Northern California into the northern Great Plains.
Dry and breezy conditions preceding this boundary will promote
elevated fire weather conditions across portions of the Great Basin
and central High Plains.
...Sierra Front into central/northern Nevada...
As the aforementioned mid/upper trough digs southward into portions
of the Great Basin, strong southwesterly flow aloft and related,
induced surface pressure falls across the Great Basin will support a
corridor of sustained southwesterly surface winds of 15-20 mph
(locally up to 25 mph) from the Sierra Front into central/northern
Nevada. Higher gusts of up to 35-45 mph (strongest along the Sierra
Front) are also expected within this corridor between the
southeastward-progressing cold front to the northwest and an influx
of greater mid/upper level moisture and cloud cover associated with
the remnants of Tropical Storm Rachel to the southeast. Coupled with
downslope drying and boundary layer mixing yielding afternoon RH
reductions to 10-15% and receptive fuels, an elevated fire weather
risk is expected this afternoon from the Sierra Front into
central/northern Nevada. Only minor adjustments were made with this
update based on the latest guidance.
...Eastern Wyoming into far southwestern South Dakota and portions
of the Nebraska Panhandle...
Lee surface troughing and modest southwesterly flow aloft in advance
of the deepening upper trough across the Northwest and an
approaching surface cold front will continue to allow for dry,
downslope flow across portions of the central High Plains. While
some uncertainty exists regarding the timing of increasing cloud
cover from the southwest and its impact on RH reductions, elevated
fire weather conditions are expected across much of eastern Wyoming
and adjacent areas of the central Plains where sustained
west-southwesterly surface winds of 15-25 mph are forecast to
overlap RH of 15-20% and receptive fuels.
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U.S. Day 2 Fire Weather Outlook
ZCZC SPCFWDDY2 ALL
FNUS22 KWNS 101929
Day 2 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0229 PM CDT Sat Oct 10 2026
Valid 111200Z - 121200Z
...Northern Sacramento Valley...
A deepening upper-level trough will settle over the northwestern
CONUS through D2/Sunday as a surface cold front pushes into northern
CA and the Great Basin. Northerly, post-frontal flow will funnel
into the northern Sacramento Valley and accelerate Sunday morning
through early Sunday afternoon. Wind speeds of 15-20 mph (25 mph
locally) with higher gusts combined with afternoon RH nearing 15%
are expected across the northern Sacramento Valley and bordering
foothills overlapping dry fuels. Only slight adjustments to the
existing elevated highlights were needed based on latest
model/ensemble guidance and trends.
..Williams.. 10/10/2026
.PREV DISCUSSION... /ISSUED 0101 AM CDT Sat Oct 10 2026/
...Synopsis...
An upper-level trough will remain in place across much of the
western U.S. on D2/Sunday, aiding in the northward transport of
deeper tropical moisture into southern California and much of the
Intermountain West. At the surface, a frontal system will extend
from southern California northeastward into the Great Basin and then
eastward into the central Plains. In the wake of this front, mainly
dry conditions will continue across the Columbia Basin and northern
California, with dry and breezy northerly flow expected to bring an
elevated fire weather threat to the northern Sacramento Valley
Sunday afternoon.
...Northern Sacramento Valley...
Following Saturday's cold frontal passage, strengthening northerly
winds and dry conditions are expected to support an increasing fire
weather threat for portions of the northern Sacramento Valley and
adjacent foothills. Sustained northerly winds of 15-25 mph (with
locally higher gusts) are forecast to overlap minimum RH values
around 20% Sunday afternoon, with the gusty winds the primary driver
of fire weather concerns where fuels are receptive.
U.S. Day 3-8 Fire Weather Outlook
ZCZC SPCFWDD38 ALL
FNUS28 KWNS 102058
Day 3-8 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0358 PM CDT Sat Oct 10 2026
Valid 121200Z - 181200Z
...Synopsis...
Widespread rainfall and higher elevation snow is expected across
much of the Intermountain West and Northern Rockies through the
middle of next week as a strong upper-level low merged with a
remnant subtropical moisture plume impacts the western CONUS. Model
guidance does suggest a period of enhanced offshore flow across
southern CA on Days 6-7/Thursday-Friday as surface high pressure and
upper ridging build over the western U.S. behind the departing upper
trough. However, preceding rainfall from Tropical Storm Rachel
should mitigate impacts from this offshore wind event. Farther east,
well above normal temperatures and dry conditions under a mid/upper
ridge will continue to bolster receptive fuels over the lower MS
River Valley northward into portions of the Midwest through Days
3-4/Monday-Tuesday. However, weak surface pressure gradients should
limit wind speeds across this region before rain potential increases
by Day 5/Wednesday.
Mid-range ensemble guidance suggests a broad ridging pattern
returning to the West late next week inviting the return of a
warmer and drier weather regime over the region. However, generally
light surface winds and marginal fuel conditions should preclude
broader fire weather concerns.
..Williams.. 10/10/2026
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