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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 080602
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0102 AM CDT Sat Aug 08 2026
Valid 081200Z - 091200Z
...Synopsis...
A large mid-level ridge will remain centered near the Four Corners
region of the US today, with the strongest mid-level flow across the
CONUS once again found along the US-Canadian border. A weak
mid-level vorticity maximum will move across the Pacific Northwest,
however mid-level flow enhancement looks modest with this feature. A
weak lower-level wave will move east from the central Rockies into
the central Plains, bringing with it a belt of modest southwesterly
low-level flow. At the same time, monsoonal moisture will continue
to advance northward across the West, bringing with it chances of
afternoon thunderstorms atop a very dry boundary layer.
... Northern Intermountain West and Pacific Northwest ...
Most of the region will see the development of surface winds around
15 mph with higher gusts as diurnal heating and the associated deep
vertical mixing bring down modest mid-level flow. The deep mixing
will also contribute to relative humidity falling to perhaps as low
as 5% in favored areas across the region, with minimum afternoon
relative humidity between 10-15% elsewhere. Given very receptive
fuels, elevated to locally critical fire weather conditions are
likely.
... California Sierras, Southern/Central Nevada, and much of Utah
...
Similar to Friday, thunderstorms are expected along the western
periphery of a mid-level ridge where the advancing mid- and
upper-level monsoonal moisture will be found. Beneath this moist
plume, a very dry sub-cloud layer will support significant
evaporation of falling precipitation leading to little, if any,
appreciable rainfall. Evaporative cooling beneath these dry
thunderstorms will result in gusty/erratic thunderstorm outflows.
... High Plains of southeast Colorado, southwest Kansas, far
northeast New Mexico, and the western Oklahoma Panhandle ...
Model guidance is in good agreement with a belt of modest
southwesterly 700-millibar flow stretching from southeast Colorado
toward the Great Lakes. This flow should easily mix down to the
surface during the afternoon as strong diurnal heating mixes into
and through this layer. The result will be gusty surface winds
between 15-20 in the presence of minimum relative humidity falling
into the teens. Seasonally adjusted ERC percentiles show a very dry
fuelscape, with percentiles between 95-98%. A small elevated area
was introduced to cover this potential.
..Marsh.. 08/08/2026
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U.S. Day 2 Fire Weather Outlook
ZCZC SPCFWDDY2 ALL
FNUS22 KWNS 080610
Day 2 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0110 AM CDT Sat Aug 08 2026
Valid 091200Z - 101200Z
...Synopsis...
A large mid-level ridge will once again be centered across the
Southwest on Sunday. Along the northern periphery of this ridge, a
series of short-wave troughs/vorticity maxima will move from the
Pacific Northwest, across the Northern Rockies, and into the
Northern Plains. Monsoonal moisture will continue to work its way
around the Southwest ridge, with some potential for dry
thunderstorms along its periphery.
... Northern California and Oregon east into far western South
Dakota and Nebraska ...
Strong diurnal heating of the dry airmass in place will result in a
deeply mixed boundary layer. This will allow the modest mid-level
flow to mix down to the surface yielding localized areas of 15-20
mph winds, with higher gusts. At the same time, minimum afternoon
relative humidity will fall into the upper single digits to teens.
The result will be a broad area of elevated to locally critical fire
conditions, particularly across terrain favored areas of Idaho and
Wyoming.
... Sierras east into Colorado ...
A mixture of wet and dry thunderstorms are expected to develop
across portions of this region on Sunday. The environment in which
these storms develop can be characterized as deeply mixed, with a
very dry sub-cloud layer. Thus, any thunderstorm that does develop
within this zone will have the potential for significant evaporation
within precipitation cores, limiting meaningful precipitation
amounts, despite precipitable water values around three-quarters of
an inch. Strong, gusty, and erratic thunderstorm outflows will be
possible with these storms.
... Portions of the Southern High Plains ...
The belt of enhanced southwesterly 700-millibar flow across
southeast Colorado on Saturday will expand south and east across the
Texas Panhandle and western Oklahoma on Sunday. As strong diurnal
heating develops during the afternoon, this wind will mix down to
the surface yielding winds around 15 mph, with locally higher gusts.
At the same time, minimum afternoon relative humidity percentages
will fall to between 10-15. Seasonally adjusted ERC percentiles show
much of the area at greater than 95%, with pockets in excess of 98%.
This combination of fuel dryness, winds, and low humidity will
result in at least elevated fire weather conditions on Sunday.
Additionally, a couple of isolated dry thunderstorms may develop
across the Plains of southeast Colorado during the late afternoon
and evening. Forecast soundings show a very deeply mixed boundary
layer (nearly to 500 millibars) with several hundred J/kg of MUCAPE
originating in the mid-levels. Sub-cloud layer mean relative
humidity less than 20% will support significant precipitation
evaporation efficiency, limiting widespread appreciable rainfall
amounts. Thus, a few lightning induced wildfire starts will be
possible with any high-based thunderstorm that develops.
..Marsh.. 08/08/2026
U.S. Day 3-8 Fire Weather Outlook
ZCZC SPCFWDD38 ALL
FNUS28 KWNS 072215
Day 3-8 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0515 PM CDT Fri Aug 07 2026
Valid 091200Z - 151200Z
...Synopsis...
A mid-level shortwave will move into the northern High Plains by Day
3/Sunday within a deamplifying upper ridge. This will leave a zonal
flow pattern in place across the northern CONUS for early next week
with lingering fire weather concerns over portions of the
Intermountain West. A dry thunderstorm threat will likely persist
across portions of the Great Basin and central Rockies on Days
3-4/Sunday-Monday on the northern fringe of deeper monsoonal
moisture across the Desert Southwest.
...Days 3-4/Sunday-Monday...
...Northern Intermountain West and adjacent northern High Plains...
A mid-level short wave should round the flattening upper ridge over
the West, affecting the Northern Rockies on Day 3/Sunday. A
tightening surface pressure gradient along the southern Cascades and
adjacent terrain will promote gusty surface winds within a dry
boundary layer. Breezy west winds up to 15 mph (locally 20 mph) and
low relative humidity will combine with increasingly receptive fuels
across the broader northwestern CONUS. As such, 40% Critical
probabilities were largely maintained for this broad region. On Day
4/Monday, stronger upper-level flow will continue across the
flattened ridge, sustaining a pattern of dry and breezy conditions
atop exceptionally dry fuels. 40% Critical probabilities have been
expanded to account for a broader, prolonged fire weather threat.
...Southern Sierra, central Nevada and portions of Utah...
High based convection is likely to evolve Days 3-4/Sunday-Monday on
the northern periphery of deeper monsoonal moisture. PWATs ranging
of 0.60-0.80" and daytime instability will likely lead to isolated
high-based thunderstorms across portions of the southern Sierra
Nevada, upper Great Basin, and northwestern CO on Day 3/Sunday. This
threat will persist across the northern Great Basin, southwestern
WY, and northwestern CO on Day 4/Monday. Uncertainty remains in the
strength and residence time of the monsoon surge, though a mix of
wet/dry thunderstorms atop a drought-stressed and significantly dry
fuel environment raises concerns for lightning-induced ignitions; as
a result, 10% Dry Thunderstorm probabilities have been expanded on
Day 3/Sunday and introduced on Day 4/Monday.
...Days 5-8...
On Day 5/Tuesday, 40% Critical probabilities were expanded across
southeastern OR, northeastern CA, and portions of the Great Basin
where forecast confidence is higher in a continuation of dry and
breezy conditions. Extended ensemble guidance depicts a pattern
change across the western CONUS late next week, with offshore
troughing bringing the potential for surging monsoonal moisture and
thunderstorms to northern California and the Pacific Northwest.
However, predictability is too low in the long term to introduce any
probabilities at this time.
..Elizalde-Garcia.. 08/07/2026
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