ACUS11 KWNS 210054
SWOMCD
SPC MCD 210053=20
NEZ000-SDZ000-210230-

Mesoscale Discussion 1218
NWS Storm Prediction Center Norman OK
0753 PM CDT Sat Jun 20 2026

Areas affected...portions of Nebraska Sandhills

Concerning...Severe Thunderstorm Watch 360...

Valid 210053Z - 210230Z

The severe weather threat for Severe Thunderstorm Watch 360
continues.

SUMMARY...An elevated supercell developed across portions of the
Nebraska Sandhills this evening. Large hail and damaging wind will
be possible as this storm moves east. Additional thunderstorms may
also develop later this evening and be capable of large hail and
damaging winds as well.

DISCUSSION...An isolated supercell has developed across the Nebraska
Sandhills. This eastward moving storm has quickly intensified, with
MRMS hail estimates approaching 2".=20

The observed 00Z sounding from North Platte, NE, indicates a
strongly sheared and modestly unstable environment across the
region. Low-levels are largely stable, with a 0-3 kilometer lapse
rate of 4 C/km beneath a strong inversion just below 700 millibars.
Thus, the ongoing supercell is elevated and likely rooted at or
slightly above this inversion. That said, parcels originating at
this level are unstable, with MUCAPE around 1200 J/kg and effective
layer shear in excess of 50 knots. This environment should support
continued hail across the area this evening. Additionally, DCAPE
from the sounding is around 1000 J/kg so isolated damaging wind
gusts are also possible.=20

With continued warm-air advection atop this stable boundary layer,
additional thunderstorms may be possible later this evening.
Additionally, a cluster of thunderstorms will move east out of
Wyoming and the Nebraska panhandle later this evening. Given the
overall environment, large hail and damaging winds would be possible
with those storms as well.=20

Recently issued Severe Thunderstorm Watch #360 was issued to address
these threats.

..Marsh/Smith.. 06/21/2026

...Please see https://urldefense.com/v3/__http://www.spc.noaa.gov__;!!DZ3fj= g!-DwYjkGD0ZyW-9X_LXpqpaxW_9OEgGLLoM4Jn6jc_N_JUW92yvrVK7vqnu11lU_UMeX6kN5y9= 31CGeD0X_WKLK_WzYE$ for graphic product...

ATTN...WFO...GID...LBF...UNR...CYS...

LAT...LON 42970277 43010026 40710021 40660124 40990127 41010256
41970269 42970277=20

MOST PROBABLE PEAK WIND GUST...65-80 MPH
MOST PROBABLE PEAK HAIL SIZE...1.50-2.50 IN


=3D =3D =3D
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.28-Linux
* Origin: Capitol City Online (1:2320/107)