SPC AC 260534
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1234 AM CDT Thu Mar 26 2026
Valid 261200Z - 271200Z
...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS
OF THE MID-MISSISSIPPI VALLEY AND OHIO VALLEY...
...SUMMARY...
Scattered severe thunderstorms are expected late this afternoon and
evening across parts of the Mid-Mississippi and Ohio Valleys. Very
large hail, a few tornadoes, and severe wind gusts will be possible.
...Mid-Mississippi Valley and Ohio Valley...
Early-morning water-vapor imagery depicts a weak short-wave trough
topping the dominant southwestern anticyclone over southern WY.
Latest lightning data supports this with isolated thunderstorms
currently noted from southern WY into the NE Panhandle. 00z model
guidance suggests this feature will advance into the Mid-MO Valley
by 18z, then progress into the Mid-MS Valley by 27/00z. As this
short wave advances east, surface ridging will build south across
the Plains and force a pronounced cold front across much of IA by
early afternoon with the sharp boundary settling south across
northern IL as a weak surface wave tracks toward southern Lower MI.
Deep westerly flow should allow surface temperatures to warm quickly
into the lower-mid 80s south of the front over IL/western IN. Even
so, convective temperatures may struggle to be breached until late
afternoon. Current thinking is upper 50s to near 60 F dew points
should return to this region prior to frontal passage, thus modest
MLCAPE is expected to develop. Forecast soundings suggest weak
capping may hold across the warm sector so it's not entirely clear
how much activity will develop well ahead of the front. However,
strong frontal forcing will easily encourage thunderstorm
development and convection will evolve within a strongly sheared
environment. Profiles favor organized rotating updrafts and
supercells are expected, especially early in the convective cycle.
Given the strength of the front there is an expectation for storm
mergers and line segments to evolve. Very large hail is possible,
especially with early supercell development. As a frontal MCS
evolves, damaging winds are expected to be more common with the LLJ
strengthening into the evening hours across the OH Valley. Some
tornado threat also exists with storms that are not undercut by the
surging cold front, both with supercells and within the extensive
frontal squall line. This activity will spread toward the Ohio River
where gradual weakening is expected during the late-night hours.
..Darrow/Chalmers.. 03/26/2026
NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 1300Z
SPC AC 260545
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1245 AM CDT Thu Mar 26 2026
Valid 271200Z - 281200Z
...NO SEVERE THUNDERSTORM AREAS FORECAST...
...SUMMARY...
Isolated thunderstorms are expected from the Ohio Valley into the
Carolinas Friday morning into the afternoon, but severe thunderstorm
potential appears limited.
...Synopsis...
A cold front noted in 05 UTC surface observations across the
northern Plains is forecast to push southeast over the next 48
hours. Thunderstorms will likely be ongoing along the front across
the OH Valley around 12 UTC Friday, but should gradually wane in
coverage from west to east through late morning as frontal ascent
shifts south into an air mass with poor mid-level lapse rates.
Heating of a seasonally moist air mass across the Carolinas and
southern Virginia (mid 50s dewpoints) will likely yield a pocket of
MLCAPE values between 100-300 J/kg ahead of the front. Isolated to
widely scattered thunderstorms are expected as the front pushes
through during the mid to late afternoon hours. While 30-40 knot
mid-level flow will overspread the region through peak heating, the
general consensus among guidance, including the typically aggressive
RRFS, is that buoyancy profiles will remain too marginal to support
intense updrafts and a more appreciable severe threat.
..Moore.. 03/26/2026
WUUS02 PTSDY2
SPC AC 260718
Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0218 AM CDT Thu Mar 26 2026
Valid 281200Z - 291200Z
...NO SEVERE THUNDERSTORM AREAS FORECAST...
...SUMMARY...
Isolated thunderstorms will be possible Saturday afternoon across
portions of the Florida peninsula, but the potential for severe
thunderstorms is low.
...Synopsis...
Dry and stable conditions will be prevalent across much of the CONUS
as a broad region of high pressure builds over the eastern Plains/OH
Valley in the wake of a strong frontal passage during the D2/Friday
to early D3/Saturday period. This front is forecast to reside across
the northern Gulf and into the northern FL peninsula by 12 UTC
Saturday, and will continue to migrate south through the day before
stalling over south FL during the evening/overnight hours. Although
forcing for ascent should steadily diminish given the frontolytic
nature of the boundary, weak low-level ascent within a moist and
weakly capped environment may support a few thunderstorms.
Displacement from stronger flow aloft will limit storm organization
and longevity, which should preclude organized convection. Based on
extended-range RRFS and MPAS solutions, as well as ensemble QPF
signals, the best potential for thunderstorms should emerge across
the Lake Okeechobee vicinity and areas westward to the FL Gulf
coast.
..Moore.. 03/26/2026
WUUS03 PTSDY3
NOTE: THE NEXT DAY 3 OUTLOOK IS SCHEDULED BY 1930Z
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