Day 1 Convective Outlook  
NWS Storm Prediction Center Norman OK
0754 AM CDT Sun Apr 12 2026

Valid 121300Z - 131200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF
TEXAS...

...SUMMARY...
Isolated to scattered severe thunderstorms are possible today into
evening mainly across parts of Texas and perhaps other nearby parts
of the southern Plains. More isolated severe storms may occur across
portions of the Upper Great Lakes and northern Rockies.

...Texas/Southern Plains...
A rather complex scenario exists early today attributable to several
factors including an MCS that de-intensified/decayed generally near
I-35 in Texas overnight, with residual cloud cover and outflow
impacts. Potentially focused in vicinity of outflow, the passing
mid-level wave and persistent warm/moist advection may support storm
persistence and redevelopment/intensification later today across
central Texas into parts of east Texas and possibly Louisiana within
a moderately unstable environment.

In the wake of the mid-level wave, mid-level height rises/subsidence
are otherwise anticipated coincident with the dryline from central
Kansas south-southwestward across western Oklahoma and
west/southwest Texas. The extent and likelihood of storm development
later today is highly uncertain, but if/where storms do form, the
environment would generally be supportive of supercells and related
hazards given ample buoyancy and moderate deep-layer shear.

...Minnesota/Wisconsin...
A surface low over the northern Plains will migrate eastward along
the U.S./Canadian border through the day, reaching northern
Minnesota by around peak heating. A narrow tongue of returning
moisture may support a corridor of sufficient ascent and buoyancy
for deep convection. A few surface-based supercells could occur
along the frontal zone where dewpoints may reach into the mid/upper
50s F. While this potential appears low/uncertain per latest
guidance, some tornado threat could materialize along the front.
Hail/wind will otherwise be possible regionally on an isolated
basis.

...Northern Rockies...
Ahead of an approaching upper wave, mid-level moisture will support
another day of fairly modest surface-based buoyancy with persistent
30-40 knot flow within the CAPE-bearing layer. Combined with
somewhat deep boundary-layer mixing, this may support strong to
severe downburst winds with the more robust convective cells, mainly
this afternoon through early evening.

..Guyer/Broyles.. 04/12/2026

Day 1 Convective Outlook  
NWS Storm Prediction Center Norman OK
1129 AM CDT Sun Apr 12 2026

Valid 121630Z - 131200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF
SOUTHWEST AND CENTRAL TX...

...SUMMARY...
Isolated to scattered severe thunderstorms are possible today into
evening mainly across parts of Texas and perhaps other nearby parts
of the southern Plains. More isolated severe storms may occur across
portions of the Upper Great Lakes and northern Rockies.

...Synopsis...
Recent satellite imagery shows a pair of phased shortwave troughs
over the Plains, one moving through the Dakotas and another moving
through KS/OK. Both of these waves are forecast to continue
northeastward through the day, with the northern wave reaching
northwestern Ontario and the southern wave reaching the Great Lakes
region. This evolution will take these waves east/northeast of the
higher low-level moisture, which will remain in a corridor from the
southern Plains northeastward into the Upper Midwest. Showers and
thunderstorms are anticipated throughout much of this corridor
today, with highest thunderstorm chances across central/east TX and
from the Upper Midwest into the Great Lakes.

Farther west, an upper low is slowly drifting eastward across
northern CA. Guidance suggests this eastward drift will continue
today, with several shortwave troughs rotating quickly through the
base of this system and ejecting across the Great Basin and northern
Rockies. Large-scale ascent and modest mid-level moisture associated
with these waves will combine with cold temperatures aloft and
associated buoyancy to support thunderstorms today from northern CA
across the northern Great Basin and northern Rockies, and into the
northern Plains.

...Southern/Central Plains...
Much of this region will be displaced south and west of any notable
large-scale forcing for ascent. This limited ascent, combined with
the showers and isolated thunderstorms currently ongoing across
central and east TX, complicates the overall forecast today, with
mesoscale factors likely contributing significantly to when and
where storms develop this afternoon and evening. General expectation
is for development along the southern and western periphery on the
ongoing storms (i.e. from southeast/south-central TX into southwest
TX) later this afternoon and this evening. This redevelopment will
be supported by a combination of moist advection, modest heating,
and limited low-level convergence. Moderate to strong buoyancy amid
moderate vertical shear could support supercells if the mode remains
discrete. However, the weakness in the mid-level flow suggests
storms may tend to cluster, a scenario that is supported by most CAM
guidance. Buoyancy and shear are still strong enough to support
rotating updrafts and large hail early in the convective cycle, but
the trends towards a messy convective mode could limit the
persistence and coverage of robust updrafts. Damaging gusts are
possible even with the clustered storm mode, especially given there
is some potential for slightly more organized bowing segments over
time.

Farther west, mid-level height rises/subsidence are anticipated
coincident with the dryline from central Kansas south-southwestward
across western Oklahoma and west/southwest Texas. The environment,
characterized by 1500 to 2000 J/kg of MLCAPE and 30 to 40 kt of
westerly deep-layer shear, is conditionally supportive of supercells
capable of all severe hazards. However, the previously mentioned
height rises and subsidence, combined with modest convective
inhibition, are generally expected to preclude thunderstorm
development. Even so, given the conditional risk, Marginal risk
probabilities will be maintained.

...Minnesota/Wisconsin...
Recent surface analysis places a low just west of FAR, with a warm
front extending southwestward across central/southeast MN and
southern WI. This low is forecast to move eastward today, while the
warm front expands northward. A narrow corridor of surface-based
buoyancy could develop from north-central MN into far northwest WI
as dewpoints increase in the upper 50s (perhaps even low 60s).
Thunderstorm initiation appears possible along the cold front within
this corridor, although veered low-level flow and northward/westward
displacement of the better forcing casts doubt to whether updrafts
will be maintained. Any storms that do mature within this warm
sector should become supercells capable of all severe hazards,
including large hail and tornadoes. However, low confidence in storm
development and maturity precludes higher probabilities with this
outlook.

...Northern Rockies...
Mid-level moisture will support another day of modest surface-based
buoyancy ahead of the shortwave trough mentioned in the synopsis.
Persistent 30-40 knot flow within the CAPE-bearing layer combined
with somewhat deep boundary-layer mixing will support strong to
severe downburst winds with the more robust convective cells, mainly
this afternoon through early evening.

..Mosier/Squitieri.. 04/12/2026

Day 2 Convective Outlook  
NWS Storm Prediction Center Norman OK
1227 PM CDT Sun Apr 12 2026

Valid 131200Z - 141200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS
OF CENTRAL/EASTERN MINNESOTA INTO WESTERN/CENTRAL WISCONSIN...

...SUMMARY...
Severe thunderstorms are likely across the Upper Mississippi Valley
and Great Lakes region with potential for large to very large hail,
damaging wind, and tornadoes. A more conditional and isolated risk
for severe storms is possible across portions of the southern Plains
on Monday.

...Synopsis...
A southwesterly flow regime will continue from the southern Plains
to the Upper Midwest on Monday. Low-amplitude upper ridging will
move across the Upper Midwest during the day ahead of a shortwave
trough moving across the northern Plains. The shortwave will shift
east across the Great Lakes overnight. Meanwhile, an upper trough
from the northern Rockies to offshore the southern CA coast will
pivot eastward toward the Four Corners region. At the surface, low
pressure near the SD/NE border will develop east along the MN/IA
border to central WI. Lee troughing will persist across the Plains.
A dryline will extend southwest from the Mid-MO Valley into western
OK/TX, while a warm front extends from southern MN into
southern/central WI. These boundaries will become a focus for severe
thunderstorm development during the afternoon/evening.

...Upper Midwest...
Along and south of the surface warm front across MN into
southern/central WI, strong daytime heating will be occurring amid
dew points in the low to mid 60s. This will yield moderate to strong
instability with MLCAPE around 2000-3000 J/kg. A plume of steep low
to mid-level lapse rates will also impinge upon the region through
the afternoon. Capping will likely suppress thunderstorm activity
for much of the day as the shortwave upper ridge moves across the
region. By the late afternoon/early evening, a shortwave trough will
overspread the region with an increase in the low-level jet.
Thunderstorm activity is expected to develop, with initially
elevated supercells likely given strong deep layer shear and
thermodynamic profiles. These will be capable of large to very large
hail (some 2-3+ inches in diameter). Should any supercells be able
to anchor to the warm front and become surface based, the threat for
a tornado or two (possibly strong) will increase given large
clockwise curved hodographs indicative of favorable low-level shear.
An Enhanced Risk was included with this outlook driven by the hail
potential. Convection will spread eastward with time into MI,
continuing to pose a risk for hail overnight. 

...Central/Southern Plains....
A conditional severe risk will extend further down the dryline into
the central/southern Plains for the afternoon/evening. Strong
daytime heating will yield very warm temperatures ahead of the
dryline but most convective temperatures are near or exceeding 90F.
Forecast soundings indicate strong capping in place across much of
the region through the afternoon with generally weak forcing for
ascent outside of the dryline circulation, which will likely inhibit
a more widespread severe risk. Nonetheless, moderate to strong
instability will overlap increasing deep layer shear as the
low-level jet increases through the evening. An isolated supercell
threat will be possible along the dryline, with greater confidence
along the Red River in northern TX/southwestern OK and further south
into Texas near the Rio Grande Valley. Should supercells develop,
the main risk will be for large to very large hail (some 2+ inches
in diameter).

..Thornton.. 04/12/2026