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U.S. & Canada 12-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 171658
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1058 AM CST Wed Dec 17 2025
Valid 171700Z - 181200Z
The previous forecast remains on track with only minor expansions
made across southeast CO/southwest KS to reflect latest high-res
guidance. 16 UTC surface observations show winds beginning to
increase along the northern CO Front Range, but the strongest winds
are expected later this afternoon (mainly between 20-00 UTC) as the
mid-level jet begins to impinge on the northern Rockies. It remains
unclear exactly how severe RH reductions will be in the lee of the
immediate front range where peak winds are expected. While some
guidance shows RH minimums near 20%, morning solutions don't appear
to be accurately capturing recent satellite trends with more
widespread cloud cover noted in GOES imagery than depicted in recent
HRRR/RRFS runs. This continues to limit confidence in the potential
for widespread critical fire weather conditions, though localized
critical conditions may emerge if sufficient clearing can occur.
Regardless, the strong winds coupled with slowly increasing ERC
values (near the 70th percentile) should still support a wind-driven
fire weather risk. See the previous discussion below for additional
details.
..Moore.. 12/17/2025
.PREV DISCUSSION... /ISSUED 1150 PM CST Tue Dec 16 2025/
...Synopsis...
A potent upper trough will move through the Northwest and reach the
Plains by Thursday morning. At the surface, a cyclone will deepen in
the northern Plains with a trough extending into the
central/southern Plains.
...Central/southern High Plains...
Strong mid-level winds will be nearly perpendicular to the Rockies.
This, coupled with a strong cross-Divide pressure gradient, will
foster strong sustained winds and stronger gusts in the immediate
lee of the terrain. Sustained 20-30 mph winds will be probable in
the terrain-favored areas. A period of wind gusts to 60-70 mph are
expected in the lower foothills. Farther east and south, 15-20 mph
will become more common. RH will be above elevated criteria in many
places, but 15-25% will be possible from Wyoming into Colorado.
Farther south, RH will more likely be around 15-20%. With fuels
having continued to dry, the strong surface winds will still lead to
elevated to locally critical fire weather.
...Piedmont...
Dry and modestly breezy conditions appear possible within the region
during the afternoon. RH could fall as low as 20-25%, but there is
variability within guidance. Winds will generally be light at around
10 mph. Locally elevated conditions are possible, but the
duration/spatial extent is too limited and uncertain for highlights.
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U.S. Day 2 Fire Weather Outlook
ZCZC SPCFWDDY2 ALL
FNUS22 KWNS 171957
Day 2 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0157 PM CST Wed Dec 17 2025
Valid 181200Z - 191200Z
...CRITICAL FIRE WEATHER AREA FOR CENTRAL KANSAS TO FAR NORTHERN
OKLAHOMA...
A Critical risk area has been introduced for portions of central KS
to north central OK for Thursday afternoon. Latest model guidance
has trended towards stronger winds within the post-frontal regime
with most solutions showing a swath of 20-25 mph sustained winds
from southern NE into northern OK. Areas along and south of the I-70
corridor will likely see RH reductions into the 15-20% range by late
afternoon, which will support an area of critical fire weather
conditions. Latest ERCs across this region continue to suggest fuels
are only modestly receptive; however, 4-inch soil moisture
percentiles range from 5-10% of normal across much of southern KS
and OK, suggesting that dormant fine fuels may see rapid drying that
could support fire spread. See the previous discussion below for
additional details.
..Moore.. 12/17/2025
.PREV DISCUSSION... /ISSUED 1157 PM CST Tue Dec 16 2025/
...Synopsis...
Within a post-cold-front regime, strong northwesterly winds will
overspread parts of the central/southern Plains on Thursday. Colder
air will filter southward, but this should be lagging behind the
front.
...Central/southern Plains...
Despite cold air advection through the day, generally clear skies
and dry air will promote RH reductions in the 20-30% range. Farther
west, into the High Plains, 15-20% RH will be possible. Guidance
does show a fair amount of variability with regard to surface
temperatures during the afternoon, especially with northern extent.
However, sustained winds/gusts will tend to be strongest in the
central Plains with weaker winds with southward extent. With fine
fuels showing sufficient dryness in some areas and the winds being
near or just above critical thresholds, elevated fire weather can be
expected from Kansas into North Texas. These conditions may extend
farther south and west, but combinations of questionable fuels and
duration limit confidence in expanding highlights into these areas.
U.S. Day 3-8 Fire Weather Outlook
ZCZC SPCFWDD38 ALL
FNUS28 KWNS 172148
Day 3-8 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0348 PM CST Wed Dec 17 2025
Valid 191200Z - 251200Z
Fire weather concerns are expected to persist through the remainder
of the work week and into the weekend across the southern Plains and
central/southern High Plains. A largely zonal upper-level flow
regime is expected to persist through early next week before broad
scale ridging becomes established over the south-central CONUS. This
synoptic regime will favor lee troughing followed by frontal
passages across the Plains with rain/snow chances for most regions,
except for the Southwest/southern Plains where dry conditions will
persist for the next several days. Long-range ensembles do show the
potential for widespread precipitation late in the forecast period
(D6/Mon to D8/Wed) for parts of the Southwest, but steady fuel
drying is anticipated for the southern Plains/High Plains through
next week.
...D3/Friday - High Plains/southern Plains...
Dry conditions will prevail across the southern Plains early
D3/Friday in the wake of Thursday's frontal passage. A surface high
shifting eastward into the lower MS Valley will promote
southwesterly winds across much of TX, OK, and KS. Coincidentally,
an upper-disturbance moving across the northern Rockies will promote
lee troughing along the High Plains, which will induce another
downslope flow regime along the central Rockies and augment the
pressure gradient over the Plains. 15-25 mph winds are anticipated
within the dry return flow regime with RH reductions into the 15-25%
range probable from the Permian Basin into western OK. In the lee of
the Rockies, confidence in RH reductions is limited, but a strong
wind signal coupled with drying fine fuels should promote at least a
wind-driven fire weather concern.
...D4/Saturday - southern High Plains...
A cold front associated with a northern Plains/Great Lakes surface
low will gradually push into the southern Plains through the day
Saturday. While confidence in how far south this front will progress
by peak heating remains uncertain, the general consensus among
guidance is that 15-20 mph westerly pre-frontal winds will support
adequate downslope warming/drying for areas of elevated to critical
fire weather conditions.
..Moore.. 12/17/2025
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