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U.S. Day 1 Fire Weather Outlook
ZCZC SPCFWDDY1 ALL
FNUS21 KWNS 161649
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1049 AM CST Tue Dec 16 2025
Valid 161700Z - 171200Z
A trio of targeted Elevated risk areas has been introduced for
portions of the central to southern High Plains. Several days of dry
conditions with intermittent downslope flow has allowed for steady
fine fuel drying along the High Plains with ERCs increasing to the
65-75th percentiles for portions of eastern CO and NM. The continued
deepening of a surface trough over the Plains today will induce
strengthening winds through the afternoon with some regions
experiencing sustained winds of 15-25 mph (gusting to 30 mph at
times). 16 UTC surface observations show RH reductions already
trending lower than anticipated by morning guidance ahead of and
behind lingering cloud cover. With further RH reductions (into the
15-25% range) likely amid daytime heating, areas of elevated fire
weather conditions appear probable for at least a few hours this
afternoon. The most favorable overlap of drying fuels, strong winds,
and dry conditions should reside across southeast WY/northeast CO,
southeast CO into northeast NM, and portions of southeast NM.
..Moore.. 12/16/2025
.PREV DISCUSSION... /ISSUED 1152 PM CST Mon Dec 15 2025/
...Synopsis...
As a strong upper trough moves into the Northwest, the upper ridge
across much of the CONUS will begin to flatten today. Surface high
pressure will generally remain in the Southeast. A weak surface
trough/front will move eastward through the Plains. Some locally dry
and breezy conditions are possible in the central/southern High
Plains. Wind speeds will be marginal outside of a few
terrain-favored zones. Locally elevated conditions could occur, but
greater fire weather concerns are not expected.
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U.S. Day 2 Fire Weather Outlook
ZCZC SPCFWDDY2 ALL
FNUS22 KWNS 161854
Day 2 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1254 PM CST Tue Dec 16 2025
Valid 171200Z - 181200Z
The previous forecast remains on track with only minor adjustments
required - mainly to better align the Elevated risk area with where
downslope winds are forecast to be the strongest within CO Front
Range. Latest forecast guidance continues to show the potential for
very strong (60-75 mph) wind gusts within the immediate eastern
slopes of the Laramie Mountains in southeast WY and along the
northern and central Front Range. RH reductions within this regime
remain somewhat uncertain with ensemble guidance showing only a weak
signal for sub-20% RH for northern and central CO. However, the
magnitude of the winds coupled with drying fine fuels may compensate
for the marginal RH values and support the potential for fire
spread, warranting the westward expansion. A southward expansion
along the Sacramento Mountains in NM was also made where downslope
warming/drying should promote RH reductions into the 15-20% range as
winds increase to 15-20 mph during the late afternoon hours. See the
previous discussion below for additional details.
..Moore.. 12/16/2025
.PREV DISCUSSION... /ISSUED 1235 AM CST Tue Dec 16 2025/
...Synopsis...
The northwestern upper trough will move into the central Rockies on
Wednesday. Strong mid-level winds will be roughly perpendicular to
the terrain. In the Plains, a surface low will develop/deepen in the
northern Plains with a trough extending into the central/southern
High Plains.
...Central High Plains...
Confidence in the degree of RH reduction is not overly high, but
given the favorable downslope wind pattern, pockets of 15-25% are
possible. With fuels continuing to dry in the region, they will be
at least marginally receptive to fire spread. Winds are the more
confident portion of the forecast. 15-20 mph can be expected for
most areas, especially the eastern Plains of Colorado. Within
terrain-favored areas, 20-25 mph is more probable along with even
higher wind gusts. These stronger winds will promote elevated fire
weather despite somewhat limited RH reduction and fuel
receptiveness.
...Southern High Plains...
RH of 10-20% can be expected within the region as temperatures
should be warmer than farther north. Winds should still be
relatively strong, particularly near the terrain. 15-20 mph will be
most common with terrain gaps likely being higher. Elevated
meteorological conditions could reach into parts of the Texas
Panhandle/South Plains, but current fuel indices suggest limited
risk for ignitions/spread at this time.
U.S. Day 3-8 Fire Weather Outlook
ZCZC SPCFWDD38 ALL
FNUS28 KWNS 162141
Day 3-8 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0341 PM CST Tue Dec 16 2025
Valid 181200Z - 241200Z
Fire weather concerns are expected to emerge across portions of the
Plains and southern High Plains through the second-half of the work
week and into the upcoming weekend. Latest long-range guidance shows
remarkable good agreement in the medium to long-range synoptic
regime evolution, depicting a transition from an active zonal flow
regime this week/weekend into broad-scale ridging across the
south-central CONUS by early next week. This pattern shift will
favor rain/snow chances for much of country except the Southwest
into much of the southern Plains where rainfall deficits are
steadily deepening and fuels are slowly drying.
...D3/Thursday - Central/southern Plains...
A strong cyclone is forecast to develop across the northern Plains
on D2/Wednesday before shifting into the upper Great Lakes region by
late D3/Thursday. A trailing cold front will push southeast across
the Plains through the afternoon, reaching the MS Valley by evening.
Vigorous low-level cold advection within the post-frontal air mass,
coupled with a strong low-level mass response in proximity to the
intensifying cyclone, will support widespread 15-25 mph
north/northwesterly winds from western KS and northwest OK into MO.
While there remains some spread regarding the coverage of the
strongest winds, the general guidance consensus is that conditions
will be dry/windy enough behind the front to support elevated to
critical fire weather conditions over a region with drying fine
fuels.
...D4/Friday - Southeast Wyoming...
A second upper disturbance is forecast to progress across the
northern Rockies early D4/Friday. This will support an intensifying
surface low over the northern Plains with an accompanying low-level
mass response over the High Plains. The combination of the
strengthening low/lee trough and zonal mid-level flow over the
terrain will support another downslope wind event in the lee of the
Laramie Mountains in southeast WY. Long-range guidance suggests
sustained winds of 20-30 mph are possible along with RH minimums in
the teens to low 20s. Preceding dry/windy days this week will help
precondition fuels and support a fire weather threat on Friday.
...D4/Friday and D5/Saturday - southern Plains...
Surface high pressure will quickly shift east into the lower MS
Valley by early D4/Friday morning just as a northern High Plains
cyclone intensifies. The combination of southwesterly flow on the
periphery of the surface high combined with falling surface pressure
over the northern/central Plains will induce a breezy and dry return
flow regime over portions of TX and OK. The signal for 15-25 mph
winds has remained consistent between deterministic solutions over
the past 24 hours, and ensemble guidance has begun to show better
consensus for 20+ mph winds across northwest TX to northwest OK
Friday afternoon. Given the gradual drying trend of fuels and the
tendency for guidance to over-forecast RH minimums within these
regimes, fire weather concerns appear probable Friday afternoon.
Dry/breezy conditions will likely persist across parts of TX on
D5/Saturday ahead of a southward moving cold front. Westerly flow
emanating out of the southern High Plains will maintain dry
conditions, and ensemble guidance hints at wind speeds approaching
20 mph. Uncertainty persists regarding the placement/progression of
the cold front by Saturday afternoon, and guidance tends to depict
slower frontal intrusions than reality. Because of this, adjustments
of the risk probabilities are expected as model consensus continues
to improve.
..Moore.. 12/16/2025
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