ACUS11 KWNS 212001
SWOMCD
SPC MCD 212001=20
ARZ000-MOZ000-OKZ000-KSZ000-TXZ000-212200-

Mesoscale Discussion 1231
NWS Storm Prediction Center Norman OK
0301 PM CDT Sun Jun 21 2026

Areas affected...Northern Oklahoma...southern Kansas...and adjacent
portions of southwest Missouri and northwest Arkansas

Concerning...Severe potential...Watch likely=20

Valid 212001Z - 212200Z

Probability of Watch Issuance...80 percent

SUMMARY...Conditions are being monitored for thunderstorm
development across northern Oklahoma, southern Kansas. While exact
timing remains uncertain, watch issuance is likely by early evening
once thunderstorms begin to mature within a favorable environment.

DISCUSSION...Latest surface observations and GOES imagery shows the
northward advancement of an outflow boundary across northern OK to
the east of a surface low in place across the far northeast TX
Panhandle. A recent 18 UTC RAOB from DDC and the presence of a
gravity wave along the OK/KS border suggests that pockets of
inhibition remain in place along/north of the boundary. However,
GOES daytime RGB imagery shows a few patches of glaciating cumulus
along and just north of the boundary to the southeast of the
Wichita, KS area - likely due to isentropic ascent over the
boundary. Continued heating through late afternoon will act to
reduce any lingering inhibition and should promote increasing
probabilities for surface-based thunderstorm development, especially
given the very warm/moist air mass in place along and south of the
boundary (MLCAPE recently analyzed near 3000 J/kg).=20

Recent forecast soundings (validated by recent KINX VWP
observations) depict a nearly zonal wind profile above 3 km with
effective bulk shear values on the order of 45-55 knots. This wind
profile will promote initial thunderstorm organization into
supercells capable of producing large to very large hail. Weak
low-level veering noted in regional VWPs may support some risk for a
brief tornado, but generally weak flow through the boundary layer
should modulate the overall tornado threat. Watch issuance will
likely be needed, but timing and placement will be conditional on
when and where intense thunderstorm development becomes more
probable along the OK/KS border.

..Moore/Hart.. 06/21/2026

...Please see https://urldefense.com/v3/__http://www.spc.noaa.gov__;!!DZ3fj= g!-O-1Xkg-xB_pDIqybKMfry-p9ib1YKRPRI9hs7PiE3HUoFVxRyOCTtLlDerc9bNGtpnhhLx_u= N3Rpl9BgkFDzOX65Sk$ for graphic product...

ATTN...WFO...SGF...TSA...ICT...OUN...DDC...AMA...

LAT...LON 36419999 36700006 37039991 37379956 37509922 37859486
37759452 37469439 37009435 36639437 36409446 36269456
36239508 36139914 36239960 36419999=20

MOST PROBABLE PEAK TORNADO INTENSITY...85-110 MPH
MOST PROBABLE PEAK WIND GUST...55-70 MPH
MOST PROBABLE PEAK HAIL SIZE...1.50-2.50 IN


=3D =3D =3D
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