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U.S. Day 1 Fire Weather Outlook
ZCZC SPCFWDDY1 ALL
FNUS21 KWNS 181652
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1152 AM CDT Mon May 18 2026
Valid 181700Z - 191200Z
...EXTREMELY CRITICAL FIRE WEATHER AREA FOR PORTIONS OF EXTREME
EASTERN NEW MEXICO...EXTREME SOUTHEASTERN COLORADO...SOUTHWESTERN
KANSAS...PARTS OF THE TEXAS AND OKLAHOMA PANHANDLES...
...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF THE SOUTHERN HIGH
PLAINS...
...Morning Update...
***Dangerous fire weather conditions expected across parts of the
southern High Plains this afternoon and evening***
...Southern High Plains...
No changes were made to the fire weather risk areas. Despite good
overnight humidity recoveries across much of the southern Plains, a
volatile fire environment is expected to evolve this afternoon as a
combination of very strong southwest winds of 25-35 mph (gusts
exceeding 40 mph) and critically low RH overlap a region of
profoundly dry fuels and active fires. Current surface observations
depict a cold front draped across the northern TX Panhandle with
weak northerly winds trailing behind, and a dryline slowly pushing
east across the Caprock. The cold front is expected to gradually
lift northward into southwest KS this afternoon as southerly winds
increase and spread over the southern Plains. Uncertainty exists in
how far north the front will lift, with some guidance portraying it
lifting to the southwest KS/OK state line and stalling for a few
hours. However, with numerous active fires and any new ignitions
this afternoon, a drastic wind shift from southwesterly to northerly
as the aforementioned front sweeps through the southern Plains this
evening could further exacerbate the fire environment and any
control efforts. The cold front is expected to progress southward
after 00z, with strong northerly winds of 20-30 mph (gusts up to 40
mph) immediately following the front, and breezy conditions
persisting overnight. See the previous discussion for more
information.
..Elizalde-Garcia.. 05/18/2026
.PREV DISCUSSION... /ISSUED 0124 AM CDT Mon May 18 2026/
...Synopsis...
***Dangerous fire weather conditions expected across parts of the
southern High Plains***
...Southwest into the southern High Plains...
A pronounced mid-level trough will eject over the Plains, resulting
in surface cyclone deepening over southwest Kansas, which will
promote widespread, dangerously dry and windy conditions across
parts of the Southwest into the southern High Plains today. A
dryline will sharpen across southwestern Kansas into far western
Oklahoma and northwest Texas by afternoon, with a very dry boundary
layer mixing up to 500 mb in the post-dryline environment. Given
strong downward mixing, as well as surface gradient flow with the
deepening cyclone, widespread 20-30 mph sustained west-southwesterly
surface winds overlapping with 5-15 percent RH is expected. These
conditions are likely for several hours across much of New Mexico,
to southwestern Kansas and points in between, necessitating the
maintenance of Critical highlights.
Extremely Critical highlights remain in place where confidence is
highest in sustained surface winds exceeding 30 mph amid
single-digit RH, and where the ERCs of fuel-loaded grasses exceed
the 95th percentile. Guidance consensus suggests that this volatile
overlap of favorable meteorological conditions and fuels will occur
over extreme eastern New Mexico into the Oklahoma/Texas Panhandles
and southwestern Kansas, immediately behind the dryline. The
combination of the very strong surface winds/RH, critically dry
fuels, and exacerbation of potential holdover fires will all support
wildfire spread at a life-threateningly fast pace. The danger to the
fire spread may be compounded later in the evening and early
overnight hours, when the surface cold front sweeps into the region,
resulting in a dramatic shift of the surface winds from westerly to
northerly, pivoting any ongoing fire fronts accordingly.
...Sacramento Valley in California...
A mid-level north-northwesterly wind maximum will overspread
northern California during the afternoon hours, when a dry boundary
layer is poised to mix up to the 700-500 mb layer. Such conditions
will encourage enough downward mixing, in tandem with downslope
flow, to support Elevated wildfire-spread conditions in the
Sacramento Valley this afternoon. Sustained northerly surface winds
in the 15-20 mph range coinciding with 15-20 percent RH will overlap
with receptive fuels for at least a few hours, warranting fire
weather highlights.
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U.S. Day 2 Fire Weather Outlook
ZCZC SPCFWDDY2 ALL
FNUS22 KWNS 181927
Day 2 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0227 PM CDT Mon May 18 2026
Valid 191200Z - 201200Z
...Afternoon Update...
Slight adjustments were made to the Elevated highlights across the
Southwest based on recent guidance. Broad southwesterly winds of up
to 15 mph will align with 15-20% RH atop dry fuels on Tuesday
afternoon. Locally critical conditions may arise in terrain-favored
areas where winds exceed 15 mph and RH decreases to near 10%,
especially within the Middle Rio Grande Valley. Farther west,
locally elevated fire weather conditions could emerge across the
wind prone areas of Southern California where offshore winds are
maximized (localized gusts exceeding 30 mph) alongside 10-15% RH
atop dry grasses and shrubs.
..Elizalde-Garcia.. 05/18/2026
.PREV DISCUSSION... /ISSUED 0150 AM CDT Mon May 18 2026/
...Synopsis...
A broad mid-level trough will meander over the Intermountain West
tomorrow (Tuesday), encouraging weak surface troughing over the
Desert Southwest. Southerly flow will increase with daytime heating
and boundary-layer mixing, with 15 mph sustained wind speeds likely
amid 15-20 percent RH. Elevated highlights were introduced for
central and southern New Mexico and immediate surrounding areas,
where fuels are dry.
U.S. Day 3-8 Fire Weather Outlook
ZCZC SPCFWDD38 ALL
FNUS28 KWNS 182117
Day 3-8 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0417 PM CDT Mon May 18 2026
Valid 201200Z - 261200Z
A progressive mid-level synoptic pattern will to transition to
quasi-zonal flow on Day 3/Wednesday. Simultaneously, a weak
shortwave trough will drift southward over the Intermountain West
and across the northern U.S. through late this week. A combination
of below normal temperatures and fairly widespread precipitation
will overspread much of the central and eastern portions of the
CONUS as synoptic flow stabilizes into the weekend. This could
briefly dampen the fire weather threat across much of the country
and support additional green up in some locations, particularly
across the northern CONUS, that have thus far been struggling to
grow fire-slowing vegetation. However, much longer duration
precipitation and cool conditions would be needed to appreciably
improve heavy dead fuel moisture and resultant ERCs.
On Day 3/Wednesday, lingering moderate southwesterly flow aloft will
encourage breezy conditions amid a dry airmass across
central-western NM and eastern AZ. 40% Critical probabilities remain
where southwest winds sustained at 10-20 mph will align with minimum
RH of 10-20% atop dry fuels. On Day 4/Thursday, persisting low RH
across the Southwest with much lighter winds will preclude the
introduction of probabilities. Beyond Day 5/Friday, guidance begins
to vary in the timing/extent of embedded shortwaves and associated
chances of precipitation. Nonetheless, the overall upper pattern
suggests dampened fire weather conditions on a broader scale through
the forecast period, in the exception of localized terrain-driven
breezy conditions across parts of the West.
..Elizalde-Garcia.. 05/18/2026
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