ZCZC SPCSWOMCD ALL
ACUS11 KWNS 161908 
SPC MCD 161908 
INZ000-KYZ000-ILZ000-TNZ000-MOZ000-ARZ000-162115-

Mesoscale Discussion 0817
NWS Storm Prediction Center Norman OK
0208 PM CDT Fri May 16 2025

Areas affected...northern Arkansas...eastern Missouri...southern
Illinois...far western Kentucky

Concerning...Tornado Watch 262...

Valid 161908Z - 162115Z

The severe weather threat for Tornado Watch 262 continues.

SUMMARY...A threat of very large hail and occasional tornadoes
persists across the watch area, and will eventually spread east into
southern Illinois and western Kentucky. Another watch will likely be
needed soon.

DISCUSSION...A rash of supercells is moving rapidly from
south-central into eastern MO, with isolated cells extending into
northern AR. These storms are ahead of a cold front/dryline where
low-level winds are veering to westerly. Meanwhile, the warm front
is now close to St. Louis, with southerly winds bringing 68+
dewpoints northward into the area.

The combination of cool midlevel temperatures and the ample boundary
layer moisture is resulting in MLCAPE values approaching 4000 J/kg.
This, in combination with effective deep-layer shear over 60 kt, is
providing an extremely favorable environment for very large hail of
3-4" diameter. 

In addition, 0-1 SRH remains in the 150-200 m2/s2 range, which is
sufficient for a tornado risk. In the near term, the greatest
tornado risk is over southeast MO, and will eventually shift into
far southern IL and western KY.

..Jewell.. 05/16/2025

...Please see www.spc.noaa.gov for graphic product...

ATTN...WFO...PAH...ILX...MEG...LSX...LZK...SGF...

LAT...LON   35439060 35429212 35529257 35799282 36319287 36829264
            37729202 38789143 39229116 39289076 39178951 38798854
            38238808 37358811 36658841 36038927 35439060 

MOST PROBABLE PEAK TORNADO INTENSITY...120-150 MPH
MOST PROBABLE PEAK WIND GUST...65-80 MPH
MOST PROBABLE PEAK HAIL SIZE...4.00+ IN

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