RSS Mesoscale Discussions from Storm Prediction Center
No watches are valid as of Sun Apr 12 12:57:02 UTC 2026.
No Mesoscale Discussions are in effect as of Sun Apr 12 12:57:02 UTC 2026.
SPC 1300Z Day 1 Outlook
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
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Day 4-8 Outlook
Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0339 AM CDT Sun Apr 12 2026
Valid 151200Z - 201200Z
...DISCUSSION...
...Day 4/Wed - Southern Plains to southern Wisconsin...
An upper trough will be oriented over the central/southern High
Plains Wednesday morning. This feature will shift east to the
Mississippi River by Thursday morning. As this occurs, strong
deep-layer southwesterly flow will overspread a moist and unstable
airmass from TX toward the Great Lakes. Some convection may be
ongoing Wednesday morning, resulting in some uncertainty regarding
airmass recovery and convective evolution during the
afternoon/evening. However, persistent southerly low-level flow
ahead of a dryline and continued warm advection should support areas
of airmass recovery. A mix of supercells and linear segments will be
possible, posing an all-hazards severe risk.
...Day 5/Thu...
Severe potential should be lower on Thursday as the upper trough and
weakens at it shifts east across the Ohio Valley. Widespread showers
and thunderstorms will be possible from parts of the Great
Lakes/Ohio Valley into the TN Valley, with modest instability and
limited heating tempering severe potential.
...Day 6/Fri - Southern Plains to Upper Midwest...
Medium range guidance has been fairly consistent the past several
forecast cycles in bringing a large-scale upper eastward from the
Rockies into the Plains Friday/Friday night. This should result in
surface cyclogenesis across portions of the Upper Midwest with a
trailing cold front extending into the southern Plains. Ahead of the
front, a seasonally moist/unstable airmass will be in place beneath
strengthening southwesterly deep-layer flow. This should support a
severe risk ahead of the front.
...Days 7-8/Sat-Sun...
The upper trough will continue east over the eastern U.S. on
Saturday and Sunday. Stronger ascent will shift northeast into
Canada. Deep-layer flow parallel to the surface front and a
narrowing warm sector should limit severe potential.
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