Day 1 Convective Outlook  
NWS Storm Prediction Center Norman OK
1259 AM CDT Sat Aug 15 2026

Valid 151200Z - 161200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM PARTS OF THE
OHIO VALLEY SOUTHEASTWARD INTO THE CAROLINAS...AND IN THE CENTRAL
HIGH PLAINS...

...SUMMARY...
Thunderstorms with severe wind gusts and isolated large hail will be
possible from late afternoon into the evening across the central
High Plains. Severe wind gusts will also be possible this afternoon
into the early evening from parts of the Ohio Valley southeastward
into the Carolinas.

...Mid Mississippi and Ohio Valleys/Central
Appalachians/Carolinas...
At mid-levels today, a broad anticyclonic flow pattern will be in
place over the eastern U.S. Within the flow, a shortwave trough will
move eastward into the lower Ohio Valley. Ahead of this feature, a
moist and unstable airmass will be located from the mid Mississippi
Valley east-southeastward into the Ohio Valley and southern
Appalachians. In the morning, a convective complex is forecast to
move eastward into the southern Great Lakes, and will likely be
associated with a potential for severe wind gusts. To the south of
this complex, a quasi-stationary front and moist axis will be
located from the lower Ohio Valley southeastward into the southern
Appalachians, along which moderate instability will develop by
afternoon. Low-level convergence near the front will be the focus
for convective development. A new complex of surface-based
thunderstorms appears likely to form near the front and move
east-southeastward from western Ohio into the Virginias during the
afternoon. Additional storms will develop along and near the
instability axis over the western Carolinas due to topographical
forcing.

Model forecasts in the moist air suggest that MLCAPE will peak in
the 2000 to 3000 J/kg range in most areas. Near the instability
axis, precipitable water values in the 1.8 to 2 inch range and
moderate deep-layer shear will likely support a threat for severe
wet downbursts. This threat should persist into the early evening
with any line segments that become sustained over the higher terrain
of the southern and central Appalachians.

...Central Plains...
West-southwesterly mid-level flow will be in place over the
southwestern and central U.S. today. At the surface, a moist airmass
will be located from the foothills of the Rockies eastward into the
central Plains. By afternoon, moderate instability will develop over
much of the region. Scattered thunderstorms will form in the higher
terrain and move eastward into the lower elevations during the mid
to late afternoon. Some RAP forecast soundings at 21Z from eastern
Colorado northward into western Nebraska have 0-6 km shear near 35
knots with steep low to mid-level lapse rates exceeding 7 C/km. This
environment will support a mixed mode with supercells and multicell
line segments possible. Supercells should be capable of isolated
large hail, while severe wind gusts will be possible with supercells
and organized multicells. The severe threat should persist into the
early to mid evening as a complex of storms moves eastward through
the central High Plains.

..Broyles/Lyons.. 08/15/2026

Day 2 Convective Outlook  
NWS Storm Prediction Center Norman OK
1210 AM CDT Sat Aug 15 2026

Valid 161200Z - 171200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE OHIO VALLEY TO THE SOUTHERN MID-ATLANTIC...AND ACROSS THE
CENTRAL HIGH PLAINS...

...SUMMARY...
Severe storms are possible across parts of the Ohio Valley to the
Mid-Atlantic, and in parts of the central High Plains Sunday
afternoon and evening.

...Midwest to Mid-Atlantic...

A couple of shortwave impulses/MCVs are expected to move across the
region on Sunday within broad, modestly enhanced deep-layer
west/northwesterly flow. One of these shortwave impulses may be
located over the Upper Ohio Valley Sunday morning, resulting in
ongoing cloudiness and possible convection across parts of PA/NJ and
the DelMarVa vicinity. This poses some uncertainty for severe
potential during the afternoon with northward extent across the
Mid-Atlantic. However, further south, stronger heating is
anticipated along with modest destabilization. A second shortwave
impulse/MCV will overspread the area by afternoon, supporting
additional thunderstorm develop over the upper Ohio Valley toward
the Blue Ridge. Sufficient clustering may occur as convection
organizes and spreads southeast through early evening, posing a risk
for damaging gusts.

Further north and west across the Lower Ohio Valley into the Mid-MS
Valley, a very moist and strongly unstable airmass will be in place
ahead of southeastward-advancing cold front. Vertical shear will
generally be weak, but scattered storms developing along the front
will be moving into a very unstable airmass with PW values
near/greater than 2 inches. This could support isolated to widely
scattered storms capable of wind damage.

...High Plains...

Easterly low-level flow will maintain a modestly moist boundary
layer on Sunday. Strong heating and steep midlevel lapse rates will
aid in moderate destabilization. Effective shear magnitudes around
30-40 kt will support organized cells moving east/southeast off
higher terrain by late afternoon through early evening. Large hail
and isolated strong wind gusts will be possible.

..Leitman.. 08/15/2026

Day 3 Convective Outlook  
NWS Storm Prediction Center Norman OK
0131 AM CDT Sat Aug 15 2026

Valid 171200Z - 181200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS THE
NORTHERN/CENTRAL PLAINS...AND THE SOUTHERN APPALACHIANS...

...SUMMARY...
Strong to severe thunderstorms are possible Monday afternoon and
evening across portions of the northern and central Plains, and
parts of the southern Appalachians/Carolinas.

...Northern/Central Plains vicinity...

An upper shortwave trough will pivot eastward across central Canada
on Monday, with weak height falls forecast across parts of the
northern/central Plains into the Great Lakes during the evening.
Modest boundary layer moisture (50s to low 60s F) is forecast ahead
of a southwestward-advancing surface front. As strong heating occurs
through the afternoon and northwesterly flow aloft increases,
moderate destabilization will support widely scattered storm
development ahead of the surface front. Steep midlevel lapse rates
and around 30 kt effective shear magnitudes suggest organized
isolated cells capable of hail will be possible, in additional to
sporadic strong outflow gusts.

...Southern Appalachians/Carolinas...

A very moist airmass will be in place across the southern
Appalachians to the Mid-Atlantic coast ahead of
southeastward-advancing surface cold front on Monday. Areas of
strong heating will support moderate to strong destabilization as
thunderstorms develop ahead of the front during the afternoon.
Vertical shear is expected to remain modest, but strong instability
amid steep low-level lapse rates and PW values near 2 inches may
support isolated strong/severe microburst winds and convection
spread southeast with time through early evening.

..Leitman.. 08/15/2026