341
ACUS01 KWNS 162002
SWODY1
SPC AC 162000

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0300 PM CDT Sun Aug 16 2026

Valid 162000Z - 171200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS WITHIN THE FRONT
RANGE AND PARTS OF THE CENTRAL/NORTHERN HIGH PLAINS...AND PORTIONS
OF THE OHIO VALLEY INTO THE MID-ATLANTIC...

...SUMMARY...
Thunderstorms with damaging wind gusts will be possible this
afternoon and early evening over parts of the Ohio Valley and
Mid-Atlantic. Large hail and isolated severe wind gusts will also be
possible across the Front Range and central/northern High Plains.

...20Z Update...
Ongoing convection within the Upper Ohio Valley vicinity continues
eastward this afternoon. Behind this convection, buoyancy has been
reduced. Wind probabilities have also been reduced, though isolated
strong to marginally severe storms are possible where some airmass
recovery has occurred. Elsewhere, the forecast remains on track with
only minor changes to the general thunderstorm forecast.

..Wendt.. 08/16/2026

.PREV DISCUSSION... /ISSUED 1144 AM CDT Sun Aug 16 2026/

...Upper Ohio Valley to Appalachians and Mid-Atlantic/Carolinas...
An MCV persists at midday across far southeast Michigan and northern
Ohio, with some recent uptick in convection ahead of it across
northern Ohio. Reference Mesoscale Discussion 1195 for short-term
details regarding a further increase in severe potential through
early/mid-afternoon within this regional corridor.

While storms have weakened, showers/cloud cover remain prevalent
near/east of the Appalachians at midday across the Mid-Atlantic
region. This will tend to limit/delay destabilization in many areas
(especially with north-northeastward extent). That said, air mass
recovery/advection is expected from the west, with ample upstream
clearing per visible satellite imagery across the Cumberland Plateau
into parts of the Allegheny Plateau. Pending the timing/location of
destabilization, some terrain/lee trough-related development may
diurnally occur, although the most prevalent/more certain scenario
may be for potentially severe storms to spread into the region this
evening. Damaging winds will be the most common hazard regionally,
although a tornado could occur, attributable to MCV-enhanced flow
and/or with any storms interacting with the effective warm front
across the Mid-Atlantic region.

...Middle Mississippi Valley including Missouri/Illinois...
An MCV over the Nebraska/Kansas/Iowa/Missouri border vicinity late
this morning will likely continue generally eastward, while probably
largely maintaining its related belt of enhanced mid-level flow as
observed from regional WSR-88D VWP data. A key downstream
uncertainty is the midday persistence of weak convection across
eastern Missouri into west/southwest Illinois, and that mid-level
lapse rates are rather poor to its north aside from some lingering
cloud cover.

More certain/greater destabilization may occur to the west across
Missouri, with the southeastward-advancing front being a focus for
renewed thunderstorm development later this afternoon and evening
amidst moderate/locally strong buoyancy. Deep-layer shear will tend
to be limited to around 30 kt in most areas, although somewhat
stronger MCV-related winds aloft may support upwards of 35-40 kt
effective shear for any storms across northern Missouri into
west-central/southwest Illinois. Bouts of damaging winds are the
most likely hazard regionally.

...Front Range/Raton Mesa and northern/central High Plains...
A relatively similar pattern/scenario as prior few days will
continue regionally, except a somewhat more northward-extent of the
severe risk (such as Black Hills vicinity) and a trend toward a more
northerly component to the flow aloft across the north-central High
Plains. At least widely scattered thunderstorm development is
expected into mid/late afternoon spanning the Front Range/Raton Mesa
vicinity northward across eastern Wyoming/southeast Montana and the
Black Hills vicinity. In the presence of upwards of 1500-2000 J/kg
MLCAPE, moderate vertical shear (30-40 kt) could support a few
supercells capable of severe hail. Isolated damaging winds will be
possible. This includes the most probable zone for gradual
upscale-growing linear cluster(s) across the south-central High
Plains/Raton Mesa vicinity including southeast Colorado/northeast
New Mexico toward the Oklahoma/Texas Panhandles and far southwest
Kansas. A couple of southeastward-moving thunderstorm clusters
capable of wind/damage may also emerge this evening out of the Black
Hills vicinity/western Nebraska.

$$