629
ACUS01 KWNS 260602
SWODY1
SPC AC 260600

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0100 AM CDT Sun May 26 2024

Valid 261200Z - 271200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR
CENTRAL/EASTERN MISSOURI...CENTRAL/SOUTHERN
ILLINOIS/INDIANA...SOUTHWEST OHIO...KENTUCKY...NORTHERN
TENNESSEE...EXTREME NORTHEAST ARKANSAS...

...SUMMARY...
Widespread strong to severe thunderstorms will be possible across
parts of the lower Missouri Valley into the Ohio and Tennessee
Valleys, later today into tonight. Multiple rounds of storms with
the threat for large hail, damaging wind gusts, and a few tornadoes
are possible from parts of east-central Missouri into
central/southern Illinois and Indiana, much of Kentucky and adjacent
portions of northern Tennessee.

...Synopsis...
A complex but potentially significant severe weather episode is
expected later today, with the greatest threat currently expected
from parts of lower Missouri and mid Mississippi Valleys into the
Ohio and Tennessee Valleys. All severe hazards will be possible,
including some threat for widespread damaging winds, isolated to
scattered very large hail, and potentially a few strong tornadoes.

A seasonably deep mid/upper-level trough (with multiple embedded
shortwaves) will move from the central CONUS eastward into parts of
the Midwest and OH/MS/TN Valleys through the day. A surface cyclone
initially centered over eastern KS will move eastward across MO
through the day, before turning northeastward toward the southern
Great Lakes region later tonight. A trailing cold front will move
southeastward across the Ozarks region and eventually into the Mid
South. A warm front initially near the OH Valley region may move
northward during the day, though its progress may be limited by the
effects of potentially widespread convection across the region.

...Parts of MO/AR eastward into the OH/TN Valleys...
The presence of intense and widespread convection across eastern
portions of the central/southern Plains late Saturday night results
in considerable uncertainty regarding the evolution of severe
potential during the D1/Sunday period.

A rather large storm cluster and possible MCS may be ongoing later
this morning across parts of MO and northern AR, with some embedded
supercell potential. Moderate to locally strong instability and
favorable low-level and deep-layer shear will support some potential
for all severe hazards with the early-morning convection. While
there may be some weakening trend through the morning,
reintensification of ongoing storms, and/or development along the
attendant outflow, will be possible by late morning into the
afternoon. There may be some tendency toward a clustered storm mode,
but wind profiles will remain favorable for supercells, and an
increasing threat for large to very large hail, damaging winds, and
a few tornadoes may evolve during the afternoon across parts of OH
Valley and potentially into portions of the Mid South/TN Valley
region.

Farther west, a shortwave embedded within the large-scale trough is
forecast to approach parts of the mid MS Valley late this afternoon
into the evening, in conjunction with the primary surface low.
Scattered thunderstorm development will be possible near the remnant
outflow generated by morning convection, as well as along the
trailing cold front. The environment across the effective warm
sector (east of the cold front and along/south of the anticipated
outflow boundary) will remain favorable for organized convection,
and initial supercell development could be accompanied by a threat
for large to very large hail and a few tornadoes. There will be some
strong tornado potential, especially if notable outflow modification
can occur through the day, though the most favored tornado corridor
remains uncertain at this time.

Eventual development of a large QLCS will be possible tonight
along/east of the surface-low track and trailing cold front, with a
continued threat for damaging wind, hail, and possibly a few
tornadoes into a larger portion of the OH/TN Valleys and Mid South.

...Northern IL into southeast WI...
A secondary area of modest pre-frontal destabilization may develop
this afternoon from northern IL into southeast WI. Modest but
sufficient deep-layer flow/shear will support some storm
organization, and a few stronger storms capable of hail and locally
strong wind gusts may develop from afternoon into the early evening.

...Eastern KS into western MO...
Lingering moisture/instability and favorable deep-layer shear behind
the cold front could support isolated strong storm development late
this afternoon into the evening from eastern KS into western MO.
Some threat for hail and locally strong/damaging gusts will be
possible within this post-frontal regime.

...Carolina Piedmont into the Mid Atlantic...
There is some potential for early-day convection to persist and
eventually spread across the southern Appalachians into parts of the
Carolina Piedmont and vicinity by late afternoon or evening. While
the environment will tend to be less favorable with southeastward
extent, some threat for damaging wind and/or isolated hail could
spread into the region later in the day.

..Dean/Moore.. 05/26/2024

$$