ACUS11 KWNS 282149
SWOMCD
SPC MCD 282149=20
INZ000-ILZ000-MOZ000-282315-

Mesoscale Discussion 2282
NWS Storm Prediction Center Norman OK
0349 PM CST Sun Dec 28 2025

Areas affected...Extreme southeast Missouri...southern and eastern Illinois...and western Indiana

Concerning...Tornado Watch 643...

Valid 282149Z - 282315Z

The severe weather threat for Tornado Watch 643 continues.

SUMMARY...The threat for occasional damaging gusts and tornadoes
with embedded circulations will continue as storms consolidate and
spread eastward across Illinois toward Indiana.

DISCUSSION...Over the past hour, a line of thunderstorms has
consolidated along the cold front moving quickly eastward across
Illinois. A corridor of weak buoyancy precedes the front, where
surface temperatures peaked in the mid 60s to lower 70s, in the
presence of lower 60s dewpoints. Recent observations from KILX
revealed a tornadic debris signature southeast-through-east of
Decatur, IL, with a circulation embedded in the line. Additional
tornadoes will be possible given the long, low-level hodographs and
substantial (200-300 m2/s2) SRH in the storm inflow, within a
sufficiently moist and weakly unstable pre-storm environment.

Additional storm development is expected farther south along the
front toward extreme southeast MO and southern IL over the next 1-2
hours. Though the loss of surface heating will result in a gradual
reduction in buoyancy with eastward extent, strong wind profiles
will help maintain the potential for a few tornadoes and damaging
gusts into late evening.

..Thompson.. 12/28/2025

...Please see https://urldefense.com/v3/__http://www.spc.noaa.gov__;!!DZ3fj= g!5Juvwo0FowmPhpp3Pk_5q8J35uN69LG2tN6gZxmJ3Z617eMTZ48AIJ3lQpONWAfL99paPmfvP= 45CWq_JkxkWT3oTmKA$ for graphic product...

ATTN...WFO...IWX...IND...PAH...LOT...ILX...LSX...

LAT...LON 40498806 41168761 41238685 40968628 39858691 38848759
37878829 37198907 37038965 37149002 37898975 39228889
40498806=20

MOST PROBABLE PEAK TORNADO INTENSITY...85-115 MPH
MOST PROBABLE PEAK WIND GUST...55-70 MPH
MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN


=3D =3D =3D
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