RSS Mesoscale Discussions from Storm Prediction Center
SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0250 PM CDT Tue Mar 10 2026
Valid 102000Z - 111200Z
...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
NORTHERN/CENTRAL ILLINOIS INTO NORTHWEST INDIANA...
...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
WEST/CENTRAL TEXAS INTO CENTRAL OKLAHOMA...AND THE MIDWEST INTO THE
GREAT LAKES...
...SUMMARY...
Scattered to numerous severe thunderstorms are expected today and
tonight from the southern Plains to the southern Great Lakes
vicinity. All severe hazards are likely, including the risk for
multiple strong to intense tornadoes, damaging winds, and very large
hail.
...20Z Update...
The majority of the forecast remains on track and is unchanged.
Modest adjustments were made to the Enhanced risk in the southern
Plains. Surface heating is increasing into more of the I-35 corridor
as clouds continue to gradually erode from west to east. As
mid-level ascent increases into the evening, there is potential for
more organized linear structures to move into central Oklahoma and
North Texas. Steep mid-level lapse rates sampled by observed
soundings and TAMDAR data suggest severe winds would be a concern
with these linear structures. Farther north and east, it appears
probable that capping will lead to decreasing storm intensity.
Additional details are found in the previous discussion. For
additional short-term, mesoscale details see MCD 186 and 187.
..Wendt.. 03/10/2026
.PREV DISCUSSION... /ISSUED 1128 AM CDT Tue Mar 10 2026/
...Midwest/Southern Great Lakes/Ohio Valley...
A weak surface low over eastern KS late this morning will translate
northeastward along a front towards northern IL through tonight.
Low-level warm/moist advection will continue today across the
Midwest/OH Valley into the southern Great Lakes, where surface
dewpoints of at least low to mid 60s will likely be present by this
evening. Large-scale ascent across this region will remain fairly
nebulous, as an upper trough ejects eastward over the northern
Plains. Still, a strengthening low-level jet across MO into IL/IN
from late afternoon into this evening should promote scattered
supercell development along/near the front in north-central IL.
Moderate to locally strong instability, steep mid-level lapse rates,
and strong deep-layer shear will all contribute to a very favorable
environment for significant severe potential. Very large hail (2+
inches in diameter) will be possible with initial supercells.
Effective SRH and related low-level shear will markedly increase
around 11/00Z and later in tandem with the strengthening low-level
jet. The supercellular tornado threat is likewise expected to
quickly increase through the late afternoon/evening, as
enlarged/curved low-level hodographs will easily support intense
low-level rotation. A focused corridor along and just south of the
front will have the best potential for multiple strong to intense
tornadoes (EF2-3+). Accordingly, greater tornado probabilities (15%)
and a categorical Moderate Risk have been included across parts of
northern/central IL into northwest IN with this update.
Convection should eventually grow upscale along/near the front late
this evening into the early morning hours on Wednesday. But, the
threat for tornadoes and severe/damaging winds will likely continue
with eastward extent across the Midwest/OH Valley, as both
sufficient instability and strong low-level/deep-layer shear will be
present across the warm sector.
...Texas into Oklahoma...
A closed mid/upper-level low over northern Mexico will move eastward
across the Southwest and southern High Plains by this evening while
devolving into an open wave. Enhanced southwesterly flow aloft and
pronounced large-scale ascent preceding the upper trough will
encourage robust thunderstorm development by mid to late afternoon
along the length of a surface dryline extending southward across
much of west TX. Steep mid-level lapse rates and strong deep-layer
shear will support updraft organization, with an attendant threat
for supercells initially. Very large hail (2-3+ inches in diameter)
will be possible with this discrete activity, before a transition to
more linear structures occurs through the evening. An increase in
the severe/damaging wind threat will likely be realized as this mode
transition occurs across parts of central TX into southern OK. Some
threat for embedded tornadoes will also exist, especially into
central TX where greater low-level moisture and shear are forecast.
A separate area of severe potential may develop this
afternoon/evening across parts of central into northeast TX in the
low-level warm advection regime. While weakly forced, there is some
chance for at least isolated supercells to develop and pose a risk
for large hail and a few tornadoes. This scenario remains uncertain,
but 5% tornado probabilities have been expanded eastward to account
for this conditional potential.
...Oklahoma/Kansas into the mid Mississippi Valley...
A dryline will be in place across western OK today, with a cold
front forecast to move slowly southward across KS and parts of MO
through tonight. While this area will largely remain between
stronger large-scale forcing to both the north and south, it appears
probable that additional thunderstorms will eventually develop this
evening/tonight along/south of the front. Tornadoes and large hail
appear possible with any sustained supercells, while damaging winds
should occur with line segments that can develop and spread eastward
through early Wednesday morning.
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SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0212 PM CDT Tue Mar 10 2026
Valid 121200Z - 131200Z
...NO SEVERE THUNDERSTORM AREAS FORECAST...
...SUMMARY...
Severe thunderstorms are not expected on Thursday.
...Synopsis...
An amplifying upper wave will continue to translate eastward across
the eastern CONUS through the day Thursday before moving off the
Atlantic Coast by late evening. At the surface, an attendant cyclone
will continue to drift north/northeast into eastern Quebec as it
begins to occlude. A trailing cold front will start the forecast
period draped from the Northeast into the Southeast states, and is
forecast to gradually shift east through the day before moving off
the East Coast and stalling across the FL peninsula as broad-scale
ascent weakens. Thunderstorms will likely be ongoing along the front
at the start of the period across portions of southeastern AL,
western GA, and the FL Panhandle. Lingering 40-50 knot mid-level
flow may support a few organized thunderstorms during the morning
hours - mainly along the I-10 corridor. However, it is unclear how
intense this activity will be given linear/clustered storm modes and
a marginal thermodynamic environment during the diurnal buoyancy
minimum. Regardless, steady weakening is anticipated through the day
as convection drifts into an environment with decreasing mid-level
lapse rates and diminishing forcing for ascent.
Across the northern High Plains, cold mid-level temperatures
associated with a clipper low may support pockets of sufficient
instability for lightning production. Steep low-level lapse rates
and strong flow within the lowest kilometer may support a few
stronger gusts, but the overall thermodynamic environment appears
too limited for risk probabilities at this time.
..Moore.. 03/10/2026
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