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U.S. Day 1 Fire Weather Outlook
ZCZC SPCFWDDY1 ALL
FNUS21 KWNS 271538
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0938 AM CST Sat Dec 27 2025
Valid 271700Z - 281200Z
The previous forecast largely remains on track. The only change was
to expand the elevated area slightly to the south and east.
A weak/diffuse dryline will develop this afternoon to the south of a
weak surface low developing across southeast Colorado and southwest
Kansas. To the west of the dryline, modest drying of the low levels
associated with gusty downslope flow will support minimum RH in the
upper-teens to mid-twenties. This, when coupled with gusty afternoon
winds, will support a few hours of elevated to perhaps locally
critical fire weather conditions.
..Marsh.. 12/27/2025
.PREV DISCUSSION... /ISSUED 1126 PM CST Fri Dec 26 2025/
...Synopsis...
An upper-level ridge over the central CONUS will gradually shift
east throughout the day, while an upper-level trough enters the
Northern Rockies and impinges on western periphery of the ridge.
This process will promote a tightening of the height gradient aloft
and enhancement of the flow, from the southern High Plains into the
central Great Plains. At the surface, a combination of lee
cyclogenesis and diurnally driven mixing west of a developing dry
line should allow for a few hours of Elevated fire-weather
conditions to develop. Sustained winds of 15-20 mph and RH values
into the low to mid 20s will be possible across portions of the
TX/OK Panhandles and vicinity where prolonged arid conditions have
led to dry/receptive fuels.
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U.S. Day 2 Fire Weather Outlook
ZCZC SPCFWDDY2 ALL
FNUS22 KWNS 271900
Day 2 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0100 PM CST Sat Dec 27 2025
Valid 281200Z - 291200Z
A strong surface cold front will rapidly move across the Southern
Plains on Sunday, ushering in a much dryer and colder airmass.
Westerly winds ahead of the front may support locally elevated fire
weather conditions during the late morning or early afternoon across
the region. In the wake of the front, strong/gusty northerly winds
between 20 and 30 mph (with gusts approaching 50 mph) will usher in
the aforementioned very dry continental airmass.
Although the post-frontal airmass will be colder than the
pre-frontal airmass, pockets of sunshine may slow the rate at which
temperatures fall during the afternoon. Thus, despite the cooler
post-frontal airmass, relative humidity should continue to fall
during the afternoon as the dryer air takes hold.
Given the ability of the Southern Plains fire environment to
overproduce the past few days, especially across portions of the
Texas Panhandle, have opted to go ahead and expand the elevated risk
area from West Texas north and east into the southeast part of the
Texas Panhandle and most of western and central Oklahoma. The
expectation is that relative humidity will be lower than currently
forecast and the very strong, gusty northerly post-frontal winds
will be sufficient to offset the slightly higher relative humidity.
..Marsh.. 12/27/2025
.PREV DISCUSSION... /ISSUED 1128 PM CST Fri Dec 26 2025/
...Synopsis...
An upper-level trough over the central/northern High Plains will
shift east into the Great Lakes and Ohio Valley region throughout
the day. At the surface, an area of low pressure will track from the
central Great Plains to the Great Lakes region. In its wake, a cold
front will sweep across much of the central CONUS, replacing near
record warmth with more seasonal temperatures.
Model guidance suggests there could be a window of up to a few hours
supporting Elevated fire-weather conditions associated with the
pre/post cold front passage, mainly across portions of the southern
High Plains. Pre-frontal residual dry air and diurnally driven winds
should be present ahead of the front by early afternoon. Then,
temperatures should remain above the minimum thresholds behind the
front for another 2-3 hours amid gusty northwest winds despite
rising RH values. Therefore, Elevated highlights have been
introduced for a small portion of West Texas and far southeast New
Mexico, confined to areas where fuels appear most receptive. The
frontal passage may at least temporarily exacerbate any ongoing
fires across the region as well.
U.S. Day 3-8 Fire Weather Outlook
ZCZC SPCFWDD38 ALL
FNUS28 KWNS 272134
Day 3-8 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0334 PM CST Sat Dec 27 2025
Valid 291200Z - 041200Z
The mid-level ridge across the central United States will finally be
suppressed to the south by the start of this forecast period as a
strong cyclone evolves across the Great Lakes. This strong cyclone
will drive a cold front southward into the Gulf of America and
through the Southeast, ushering in a cold, dry continental airmass
across much of the eastern US. Despite the cooler airmass, elevated
to locally critical fire weather conditions may develop across
portions of the Southern Plains on Monday (D3) and Tuesday (D4).
On Monday the dry airmass will be fully entrenched across the Plains
as a strong surface anticyclone takes hold from the Northern Plains
into the Southern Plains. The result will be minimum afternoon
relative humidity will be lower than on Sunday, falling into the
teens and twenty percent range. Winds, however, will be considerably
weaker than on Sunday, with maximum gusts likely in the 10-20 mph
range. The result will be elevated to locally critical fire
conditions for at least a couple of hours during the afternoon.
On Tuesday the center of the surface anticyclone will slide east of
the Plains resulting in winds turning to the west and southwest.
This will set the stage for a potential dry return flow regime
across western Oklahoma. Minimum relative humidity will once again
be in the teens in the presence of potentially gusty afternoon
winds. This may once again result in elevated to locally critical
fire weather concerns.
Through the rest of the forecast period, the large-scale pattern
across the CONUS will consist of a northwest flow regime owing to a
western ridge and eastern trough. The northwest flow pattern will
limit appreciable moisture return into the eastern US, such that any
embedded disturbance within the larger-scale flow pattern could
result in elevated fire weather concerns. However, the subtlety of
any of these features is such that the timing of any such feature is
below the scale of predictability at these time ranges.
..Marsh.. 12/27/2025
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