SPC AC 251951
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0251 PM CDT Fri Sep 25 2026
Valid 252000Z - 261200Z
...NO SEVERE THUNDERSTORM AREAS FORECAST...
...SUMMARY...
Organized severe thunderstorms are not expected today.
...20z Update...
No changes were made to the existing outlook with this update as the
forecast remains largely on track. Isolated thunderstorm development
is noted across portions of western Oklahoma as of 1945 UTC, but
cloud cover continues to generally temper surface heating ahead of
this activity. While a stronger gust or two may still be possible
(particularly where any developing convection can interact with
pockets of stronger heating/greater low-level lapse rates), the
overall severe risk continues to appear limited owing to the
marginal thermodynamic/kinematic environment.
While the overall environment is marginally more favorable farther
southwest across portions of southeast NM/West TX, relatively poor
mid-level lapse rates and the displacement of better synoptic-scale
forcing for ascent farther to the northwest suggest that convection
will largely be tied to terrain influences. Coupled with a
relatively narrow zone of greater buoyancy (as depicted by 19z
objective analysis), this suggests that the overall severe risk
should remain limited.
See the discussion below for additional details.
..Chalmers/Dean.. 09/25/2026
.PREV DISCUSSION... /ISSUED 1109 AM CDT Fri Sep 25 2026/
...Synopsis...
An MCS is decaying across the TX Panhandle/South Plains late this
morning. Outflow associated with this area of convection is
spreading south and east, while areas of rain and cloud cover slowly
develop northeastward toward western OK. In the wake of this early
day convection, some airmass recovery and modest destabilization is
possible across southeast NM into far southwest TX where stronger
heating is occurring amid more scattered cloudiness. Likewise,
across western OK ahead of the TX Panhandle convection and outflow,
more isolated cloud cover is allowing for stronger heating of a
moist boundary layer.
...Southeast NM/Southwest TX...
Midlevel lapse rates are expected to remain modest and MLCAPE will
range from 500-1000 J/kg by mid/late afternoon. Isolated convection
may develop near higher terrain initially across southeast
NM/southwest TX. A storm or two could briefly become strong and
produce marginal hail, but the severe risk is expected to be
tempered by the marginal thermodynamic/kinematic parameter space in
the wake of the early day MCS.
...Western OK...
While currently mostly sunny across western OK, afternoon heating
could become muted by cloud cover as showers associated with the
ongoing TX Panhandle activity spread east/northeast the next few
hours. This could limit stronger destabilization/steepening of
low-level lapse rates within a modestly sheared environment. A
strong gust or two could occur if sufficient heating/steepening of
low-level lapse rates unfolds. However, given modest vertical shear,
weak midlevel lapse rates, and marginal instability, the overall
severe risk appears limited.
NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 0100Z
SPC AC 251726
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1226 PM CDT Fri Sep 25 2026
Valid 261200Z - 271200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS LATE SATURDAY
AFTERNOON/EVENING FROM NORTHWEST TEXAS INTO CENTRAL KANSAS...
...SUMMARY...
Isolated hail and strong outflow winds may accompany thunderstorms
across portions of the central and southern Plains Saturday.
...Synopsis...
A persistent moisture plume and associated midlevel trough will be
shunted eastward into the southern/central Plains as upstream
heights rise over the southern Rockies, east of another weak trough
just off the northern CA coast. A deep occluding cyclone will
remain just off the northern Mid-Atlantic coast. In a warm
advection regime near the southeast New England coast, midlevel
buoyancy/depth could be sufficient for a few lightning flashes with
elevated convection. A trailing cold front will drift southward
into the FL Straits. Some air mass modification is expected along
the southeast FL coast, where a confluence zone could support
low-topped, warm process convection. However, a pronounced midlevel
inversion will likely preclude sufficiently deep convection for
charge separation.
...Southern/central Plains late Saturday afternoon/evening...
Surface-based thunderstorm development will be possible late
Saturday afternoon into Saturday evening within the lingering
moisture plume and along a surface trough from northwest TX into
central KS. A deep, surface mixed layer in areas with less cloud
debris will favor isolated strong outflow gusts. The larger-scale
mass response will remain weak, though vertical shear will be
marginally favorable for some storm organization and an associated
threat for isolated large hail.
..Thompson.. 09/25/2026
WUUS02 PTSDY2
NOTE: THE NEXT DAY 2 OUTLOOK IS SCHEDULED BY 0600Z
SPC AC 251926
Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0226 PM CDT Fri Sep 25 2026
Valid 271200Z - 281200Z
...NO SEVERE THUNDERSTORM AREAS FORECAST...
...SUMMARY...
Severe thunderstorms are not expected on Sunday.
...Synopsis...
Changes to the large-scale pattern will be slow Sunday into early
Monday with an occluded cyclone expected to remain near the northern
Mid-Atlantic coast. A midlevel shortwave trough will progress
inland to CA/NV, with downstream ridging from the southern High
Plains to the upper MS Valley. A weakening surface front will stall
near the I-44 corridor from MO into OK, and a warm advection regime
will develop late in the period across the Dakotas.
Isolated lightning flashes still may occur with elevated convection
near the southeast New England coast in association with warm
advection. A few thunderstorms will be possible through the day
Sunday from MO into OK and north TX along the weakening front.
Elevated thunderstorms will be possible Sunday night into the
Dakotas where sufficient moistening occurs with strengthening warm
advection. A few diurnal thunderstorms will be possible from
southeast AZ into NM and far west TX within the lingering monsoonal
moisture plume. The threat for isolated thunderstorms may persist
through late Sunday/early Monday into more of the Rockies as
moisture and ascent increase gradually downstream from the CA/NV
midlevel trough. Severe thunderstorms are not expected as a result
of consistently weak buoyancy and vertical shear in all of the
aforementioned areas.
..Thompson.. 09/25/2026
WUUS03 PTSDY3
NOTE: THE NEXT DAY 3 OUTLOOK IS SCHEDULED BY 0730Z
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