Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0256 PM CDT Sat Aug 01 2026
Valid 012000Z - 021200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE OHIO AND TENNESSEE VALLEYS...
...SUMMARY...
Thunderstorms with severe wind gusts and an isolated tornado threat
are expected across parts of the Ohio and Tennessee Valleys this
afternoon into evening. Isolated severe wind gusts will also be
possible in parts of New Mexico, southeast Arizona, and far West
Texas.
...20Z Update...
The MRGL Risk/5-percent wind probabilities were expanded westward
into parts of central MS, where a very warm and moist PBL (upper 70s
dewpoints) are contributing to moderate-strong surface-based
buoyancy. Any thunderstorm clusters that evolve along/ahead of the
approaching cold front will pose a risk of locally damaging wind
gusts later this afternoon and evening. Elsewhere, the forecast
remains on track, and only minor adjustments were made.
..Weinman.. 08/01/2026
.PREV DISCUSSION... /ISSUED 1116 AM CDT Sat Aug 01 2026/
..OH and TN Valleys...
Recent satellite imagery shows a positively tilted shortwave trough
moving through the Mid MS Valley. Surface analysis shows an occluded
surface low over central IL beneath the shortwave. Expectation is
for this cyclone to drift slowly east-southeastward throughout the
day, with the surface low gradually filling. As this low fills, the
triple point low, currently near the IL/IN/KY border intersection,
will become more prominent through the afternoon before it too
occludes.
Showers and thunderstorms are currently ongoing from eastern
IN/western OH through eastern TN into AL, along the eastern
periphery of an arcing warm conveyor. These showers and
thunderstorms should continue northeastward/eastward as the entire
system drifts east-southeastward, with some modest moisture
advection anticipated throughout the warm sector. This should allow
the warm sector to at least moderately destabilize, but persistent
cloudiness will limit heating, likely tempering the overall
buoyancy. Expectation is for more modest buoyancy (i.e. MLCAPE
around 500 to 1000 J/kg) across IN and OH, with greater buoyancy
(i.e. MLCAPE around 1500 J/kg) farther south across central KY and
Middle TN. Thunderstorm development is anticipated along and ahead
of the cold front as it moves through this destabilized and buoyant
airmass.
Moderate mid-level flow throughout the base of the Mid MS Valley
shortwave trough will spread eastward across KY and TN, supporting
effective shear around 30 to 35 kt across KY. Reduced vertical shear
is expected farther north across the OH Valley (due to weaker
mid-level flow) and farther south across TN Valley (due to more
westerly low-level flow). Given these kinematic conditions, a
predominantly multicellular mode is favored, although a few
supercells appear possible from southeast IN/southwest OH through
central KY. Damaging wind gusts will be the most prominent hazard,
but a tornado or two is also possible, particularly within the
corridor from far southeast IN through far north-central KY and far
southwest OH. Here, some modestly increased low-level shear is
possible near the triple point low as it moves through.
...Eastern AZ through NM into west TX...
Moderate mid-level moisture will support afternoon thunderstorm
development across the higher terrain from western AZ through
central/northeast NM. Relatively strong northerly winds aloft will
aid storm organization/clustering as storms spread
south-southeastward into the deeply mixed boundary-layer across the
lower elevations. Outflow-dominant storm structures will result in
strong cold pools capable of isolated strong to severe wind gusts.
Resulting forward-propagating lines could reach as far
south/southeast as Far West TX by later this evening.
Read more CHECK UPDATE ZOOM GRAPHIC
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