ACUS11 KWNS 160027
SWOMCD
SPC MCD 160027=20
SDZ000-NEZ000-MTZ000-WYZ000-160200-

Mesoscale Discussion 1306
NWS Storm Prediction Center Norman OK
0727 PM CDT Sun Jun 15 2025

Areas affected...northeast Wyoming and western half of South Dakota

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

Valid 160027Z - 160200Z

Probability of Watch Issuance...95 percent

SUMMARY...Thunderstorms capable of producing large hail and damaging
winds will continue to develop this evening across Wyoming before
spreading east into South Dakota. A Severe Thunderstorm Watch will
be needed shortly.

DISCUSSION...Thunderstorms are increasing in coverage and intensity
this evening across portions of northeast Wyoming. This appears to
be in response to increased ascent from the approaching shortwave
trough and a strongly buoyant and sheared atmosphere. (This
evening's observed Rapid City, SD, sounding has nearly 2700 J/kg of most-unstable CAPE and 35 knots of effective-layer shear.)

Thunderstorms will continue to intensify and increase in number this
evening within this environment. With time, expectation is to
develop one or more clusters/bowing segments that should move
east-northeast out of Wyoming and into western South Dakota. After
this, guidance is split as to whether these potential bowing
segments remain discrete or interact/merge with potential MCSs
across both North Dakota (from the Montana thunderstorms within
Severe Thunderstorm Watch #418) and southern South Dakota/northern
Nebraska (associated with a potential MCS within Severe Thunderstorm
Watch #420).

Damaging winds and large hail will be possible initially, with a
tendency to favor an increasing wind threat with time.

..Marsh/Smith.. 06/16/2025

...Please see https://urldefense.com/v3/__http://www.spc.noaa.gov__;!!DZ3fj= g!7KzXxm0wba4AmDh7tS2KOIG3RNHlPL0-gGluowWgRYyt2hRQJfAYmCbJC8AwSEDaRH7j9y4xe= ReOD9zoRNcv95eQvYE$ for graphic product...

ATTN...WFO...ABR...LBF...UNR...CYS...BYZ...RIW...

LAT...LON 42630493 43110634 44800545 45840222 45089987 43170051
42630493=20

MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 95 MPH
MOST PROBABLE PEAK WIND GUST...75-90 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 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)