Mesoscale Discussion 1090

Issued

Jun 25, 2021, 11:56 AM CDT (16:56 UTC)

Expired

Jun 25, 2021, 2:30 PM CDT

In force

3 hr

Issued by

the Storm Prediction Center

Concerning

Severe potential...watch possible

Chance of a watch

60%

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• Severe Thunderstorm Watch 314Jun 25, 1:40 PM CDT

810 
ACUS11 KWNS 251656
SWOMCD
SPC MCD 251656 
MOZ000-KSZ000-251930-

Mesoscale Discussion 1090
NWS Storm Prediction Center Norman OK
1156 AM CDT Fri Jun 25 2021

Areas affected...Much of east central into southeastern
Kansas...southwestern/west central Missouri

Concerning...Severe potential...Watch possible 

Valid 251656Z - 251930Z

Probability of Watch Issuance...60 percent

SUMMARY...Increasing thunderstorm development is expected through
1-3 PM CDT, including potential for isolated supercells, before
activity begins to consolidate into organizing clusters, with strong
wind gusts becoming the more prominent potential severe weather
hazard later this afternoon and evening.  Timing of a possible
severe weather watch issuance remains unclear, but one probably will
be needed by late afternoon, if not earlier.

DISCUSSION...Beneath modestly steep lower/mid tropospheric lapse
rates associated with a plume of warm elevated mixed-layer air, a
moist boundary layer (including lower/mid 70s F surface dew points)
appears characterized by large CAPE (in excess of 2500-3000 J/kg),
south of at least a couple of remnant outflow boundaries.  One,
south/southwest of the Lake of the Ozarks into southern portions of
the Greater Kansas City area, remains fairly prominent, with the
influence of precipitation still in the process of diminishing. The
other boundary, southwest of Kansas City into areas south and west
of Great Bend, appears more subtle, but is becoming a focus for
stronger differential surface heating.

Meanwhile, low amplitude/weak mid-level troughing, with smaller
scale perturbations, is in the process of overspreading the central
Great Plains.  This appears to have provided support for ongoing
isolated thunderstorm development across north central Oklahoma,
with at least attempts at new initiation northeast of Hutchinson and
Wichita, closer to the western outflow boundary.

While spread exists among the various model output concerning
convective evolution, there does appear a consistent signal that a
more substantive increase in thunderstorm development is possible as
18-20Z.  It seems most likely that this will be focused along and
just to the cool side of the outflow boundaries, aided by lift
associated with warm advection, and where deep-layer shear is
strongest beneath 25-30+ kt west-southwesterly deep layer mean
ambient flow.  Gradually, the surface boundary intersection near/
south of the Kansas City area may become one focus for consolidating
thunderstorm development later this afternoon.

Initial storm development may include isolated supercells posing a
risk for severe hail, with perhaps some potential for a tornado,
particularly where low-level shear appears more favorable along the
outflow boundary south/southeast of Kansas City.  However, strong
wind gusts associated with downbursts and strengthening surface cold
pools will become the more prominent severe hazard as convection
grows upscale later this afternoon.

..Kerr/Guyer.. 06/25/2021

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

ATTN...WFO...SGF...EAX...TOP...ICT...

LAT...LON   39309544 39189447 38419267 37249310 37689510 37449710
            38279766 38849707 39139602 39309544

Mesoscale Discussions in Kansas, 2021Mesoscale Discussions in Missouri, 2021Every mesoscale discussion in 2021

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.