Day 1 Convective Outlook  
NWS Storm Prediction Center Norman OK
0100 AM CDT Tue May 26 2026

Valid 261200Z - 271200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
WEST AND SOUTHWEST TEXAS...

...SUMMARY...
Thunderstorms with large hail, severe wind gusts and a couple
tornadoes are expected this afternoon and evening across parts of
west and southwest Texas. Isolated severe gusts and a marginal
tornado threat will be possible in parts of Kentucky. Isolated
severe gusts and hail may also occur in parts of the Upper Midwest
and northern Rockies.

...West and Southwest Texas...
A mid-level shortwave trough will move eastward today across far
west Texas. At the surface, a low will deepen near Big Bend as an
axis of low-level moisture sharpens from the Rio Grande Valley
northward into west Texas. Along this axis, surface dewpoints will
be in the upper 60s and lower 70s F, which will contribute to
moderate instability by afternoon. Near the moist axis, a
north-to-south corridor of low-level convergence is forecast, along
which thunderstorm development is expected by late morning. Storm
coverage is forecast to expand and move eastward from west Texas
into southwest Texas this afternoon.

Along the instability axis, MLCAPE is forecast to peak in the 2000
to 3000 J/kg range during the mid to late afternoon. RAP forecast
soundings near the instability axis at 21Z have 0-6 km shear in the
30 to 40 knot range with 700-500 mb lapse rates around 7.5 C/km.
This will be favorable for supercells with large hail. Hailstones
greater than 2 inches in diameter will be possible with the more
intense storms. In addition, forecast hodographs are curved and 0-3
km storm-relative helicity is forecast to increase to above 200
m2/s2, which will support a tornado threat. Cells are expected to
merge into a line during the late afternoon, potentially increasing
the threat for severe gusts. This line is forecast to move across
southwest Texas during the early evening.

...Kentucky...
South-southwesterly mid-level flow will be in place over the Ohio
and Tennessee Valleys today. At the surface, a mesolow is forecast
to develop over far western Kentucky this afternoon. To the east of
the low, moisture advection will increase surface dewpoints to near
70 F across much of Kentucky, where MLCAPE is forecast to peak
around 1000 J/kg. Within this unstable airmass, low-level flow over
southern and central Kentucky will be backed to the south-southeast.
This, combined with increasing low-level flow, will create curved
hodographs. Forecast soundings at 21Z south of Lexington have 0-3 km
storm-relative helicity increasing to 150 m2/s2 by mid afternoon,
which should support a marginal tornado threat. Isolated severe wind
gusts will also be possible.

...Upper Midwest...
Mid-level flow will be westerly today across much of the Upper
Midwest. At the surface, a quasi-stationary frontal boundary will be
in place from eastern North Dakota to northern Wisconsin. South of
this front, surface dewpoints in the 60s F will contribute to
pockets of moderate instability by afternoon. Scattered
thunderstorms will develop across this unstable airmass and move
east-southeastward during the afternoon. MLCAPE in some areas are
forecast to peak in the 1500 to 2500 J/kg range, with low-level
lapse rates becoming steep. This will be sufficient for isolated
severe gusts. Hail will also be possible, mainly from southeast
Minnesota into Wisconsin, where some models suggest instability will
be stronger.

...Northern Rockies...
A mid-level low will move southward across northern California
today. To the northwest of the low across the northern U.S., flow
will be from the south-southeast. At the surface, a low will deepen
across western Montana with upslope easterly flow located over much
of western Montana. As surface heating takes place today, an axis of
instability is forecast from northwest Montana extending
southeastward into far northwest Wyoming. Scattered thunderstorms
will develop in the higher terrain and move northward along and near
this axis of instability. Low-level lapse rates will be very steep,
which will contribute to a potential for severe wind gusts. Hail
will also be possible, mainly over western Montana where instability
is forecast to be the strongest.

..Broyles/Chalmers.. 05/26/2026

Day 1 Fire Weather Outlook  
NWS Storm Prediction Center Norman OK
1257 AM CDT Tue May 26 2026

Valid 261200Z - 271200Z

...Synopsis...
A robust upper level low will shift southward into the Great Basin
as a blocking ridge begins to establish over the central CONUS. Weak
upper troughing will also persist across the southern High Plains.
Meanwhile, a surface low will develop across the northern High
Plains as a cold front progresses eastward across the Great Basin.
Additional chances for wetting rainfall/thunderstorms are expected
across south-central Texas in association with a passing shortwave
trough and across much of the Southeast. 

...Great Basin...
Southwesterly flow aloft and a deepening surface low will promote a
strengthening surface pressure gradient across the region. Ahead of
an eastward progressing cold front, sustained southwesterly surface
winds of 20-30 mph are expected and a deeply mixed and dry boundary
layer will support RH reductions of 15-20%. These conditions will
promote an elevated to locally critical fire weather threat amid
cured/drying fine fuels, primarily in lower elevation/mid-slope
areas. Only minor adjustments were made to the Elevated highlights
based on recent guidance. 

...Northeastern Montana and Extreme Western North Dakota...
As the upper level trough in the Pacific Northwest progresses
southeastward towards the Great Basin, pronounced lee surface trough
development is expected across central MT. As a result,
southeasterly winds will accelerate to 15-20 mph across much of the
northern High Plains, while limited low-level moisture return will
support RH reductions to 15-20% during peak afternoon heating across
eastern MT. Delayed green up and existing dry fuels align with these
dry and breezy conditions, maintaining Elevated fire weather
highlights. Afternoon heating and resultant instability may support
isolated thunderstorm development along far southern and western MT.
Forecast soundings depict a prominent dry sub-cloud layer and PWATs
of 0.5-0.8", allowing some threat of dry thunderstorms to evolve.
However, sufficient green-up and less receptive fuels may otherwise
mitigate a broader IsoDryT threat.

..Elizalde-Garcia.. 05/26/2026

...Please see www.spc.noaa.gov/fire for graphic product...

Day 2 Fire Weather Outlook  
NWS Storm Prediction Center Norman OK
1258 AM CDT Tue May 26 2026

Valid 271200Z - 281200Z

A nearly stationary upper level low will hover over the CA/Great
Basin region through Day 2/Wednesday as an upper ridge will continue
to reside across the central CONUS. Strengthening southerly flow
aloft and tightening surface pressure gradients east of a persisting
surface low will promote a fire weather threat for portions of the
Southwest and Upper Colorado River Basin. Farther east, a weak
shortwave is expected to eject across the central and southern
Plains, bringing additional chances of appreciable precipitation to
a drought-stressed landscape.

...Eastern Great Basin and Southwest...
Broad southwesterly flow associated with the hovering upper low will
sustain fire weather concerns for portions of the eastern Great
Basin and Southwest. Southerly surface winds of 15-20 mph and RH
reductions of 10-20% will promote Elevated to locally critical fire
weather conditions amid available dry fuels.

...Northeastern Montana...
Prolonged lee surface troughing and increasing mid level flow should
support gusty surface winds across eastern MT. However, recent
guidance portrays increasing low-mid level moisture as flow
transitions southeasterly. Modest surface RH of 30-40% may alleviate
broader fire weather concerns, though elevated conditions may arise
if moisture does not advect as far north as guidance depicts. Trends
will be monitored for future outlook cycles.

..Elizalde-Garcia.. 05/26/2026

.PREV DISCUSSION... /ISSUED 0226 AM CDT Mon May 25 2026/

...Synopsis...
A robust upper-level trough will shift southward into the Great
Basin on D2/Tuesday as a blocking ridge begins to establish over the
central CONUS. Weak upper troughing will also persist across the
southern High/Great Plains. Meanwhile, a surface low will develop
across the northern High Plains as a cold front progresses eastward
across the Great Basin. Additional chances for wetting
rainfall/thunderstorms are expected across the southern High Plains
in association with a passing shortwave trough and across much of
the Southeast.

...Northeastern Montana...
Increasing southeasterly flow ahead of an evolving lee
trough/strengthening surface low is expected across much of the
northern High Plains on D2/Tuesday, with sustained surface winds of
around 15-25 mph and occasional wind gusts up to 30 mph expected.
Greater low-level moisture is forecast to remain displaced to the
east across the Dakotas, with forecast guidance/soundings depicting
deep, well-mixed boundary layer profiles and RH reductions to near
15% across much of eastern/northeastern Montana. With dry fuels
across much of northeastern Montana, these conditions are expected
to support elevated to locally critical fire weather concerns
Tuesday afternoon. Consideration was given to a westward expansion
of elevated highlights; however, uncertainty regarding the
coverage/development of high-based convection in association with a
northward shifting mid-level shortwave trough also increases with
westward extent. Trends will be monitored for future outlook cycles.

...Great Basin...
As the aforementioned upper-level trough shifts southward into the
Great Basin on Tuesday, a deepening surface low will promote a
strengthening surface pressure gradient ahead of the eastward
progressing cold front. Sustained southwesterly surface winds of
20-30 mph are expected amid this strengthening gradient, with
well-mixed boundary layer profiles supporting RH reductions to
15-20% (locally lower). Accelerating mid-level flow may also support
occasional wind gusts to 30-35 mph (perhaps higher in exposed,
elevated terrain areas). With near critically dry fuels across the
region, these conditions are expected to support a broad area of
elevated fire weather concerns, with locally critical conditions
possible in areas of drier fine fuels.

...Please see www.spc.noaa.gov/fire for graphic product...