ZCZC SPCSWOMCD ALL
ACUS11 KWNS 271604 
SPC MCD 271604 
ILZ000-MOZ000-ARZ000-OKZ000-KSZ000-271730-

Mesoscale Discussion 0763
NWS Storm Prediction Center Norman OK
1104 AM CDT Thu May 27 2021

Areas affected...portions of southeastern Kansas and northeastern
Oklahoma across the Ozarks and into parts of southern Illinois

Concerning...Severe potential...Watch likely 

Valid 271604Z - 271730Z

Probability of Watch Issuance...80 percent

SUMMARY...A gradual increase in storm coverage/intensity -- and
attendant severe risk -- over the next couple of hours will likely
require WW issuance

DISCUSSION...Latest visible satellite imagery shows
widespread/ongoing convection and attendant cloud cover, and several
outflow boundaries, from southeastern Kansas and Oklahoma east to
the mid Mississippi Valley.  The ongoing convection is occurring
south and east of a cold front extending from a low in southwestern
Iowa, southwestward across Kansas to the Texas Panhandle.  

Ahead of a loosely continuous, composite outflow boundary arcing
from northwest of St. Louis westward to southwestern Missouri, and
then into northeastern Oklahoma, some heating/destabilization is
underway -- particularly from southern Illinois westward across the
Ozarks.  This trend should continue, resulting in a gradual increase
in convective coverage and intensity over the next couple of hours.

Area VWP data indicates around 30 kt low-level south-southwesterly
flow across the warm sector, veering to west-southwesterly at mid
levels.  This is providing sufficient shear for organized/mixed-mode
convection, and therefore expect severe potential -- mainly in the
form of damaging winds and hail -- to gradually increase in concert
with convective intensification.  As such, expect WW issuance to be
required within the next hour.

..Goss/Hart.. 05/27/2021

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

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

LAT...LON   39608808 40009045 38679126 37909259 37659378 37619509
            37309588 36059652 35519449 35509176 36539017 39608808 

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