ACUS11 KWNS 210308
SWOMCD
SPC MCD 210308=20
MNZ000-NDZ000-210445-

Mesoscale Discussion 1390
NWS Storm Prediction Center Norman OK
1008 PM CDT Fri Jun 20 2025

Areas affected...Southeast North Dakota

Concerning...Tornado Watch 448...

Valid 210308Z - 210445Z

The severe weather threat for Tornado Watch 448 continues.

SUMMARY...A pair of long-lived supercells will reside within a
favorable tornado environment for at least the next 1-2 hours before
merging with an approaching MCS.

DISCUSSION...Over the past two hours, a pair of long-lived
supercells (one of which has a history of producing 2-3 inch hail
and multiple tornadoes) have meandered slowly east/southeastward
along the I-94 corridor and are moving towards a regional buoyancy
maximum (MLCAPE estimated to be around 4000 J/kg) driven by rich
low-level moisture (dewpoints in the low 70s). This rich moisture
will help modulate the influence of nocturnal low-level
stabilization and help maintain very buoyant near-surface parcels. Additionally, the approach of a mid-level perturbation from the west
is inducing a low-level mass response that is resulting in a
strengthening of the low-level jet - and consequently increasing
low-level SRH - as sampled by recent KABR VWP observations. These
trends suggest that the downstream environment may become
increasingly supportive of tornadic supercells in the short term.
Given this environment and velocity imagery from KMVX, it is
estimated that strong (EF-2 to EF-3) tornadoes will remain possible.
With time, these supercells will eventually merge with the
approaching MCS from the west. Based on recent storm tracks, this
appears most probable during the 04-05 UTC time frame, at which
point the primary threat will become widespread severe winds.

..Moore.. 06/21/2025

...Please see https://urldefense.com/v3/__http://www.spc.noaa.gov__;!!DZ3fj= g!98q4l6g29aTNahMFCC4-r3OrFjcqAJnLqDp9zCVAnumoQCoXr4m9snCFJZLgUMwccpVFeeMSo= JMw-6miB75Q3_XAWsI$ for graphic product...

ATTN...WFO...FGF...BIS...

LAT...LON 46269797 46399824 46629828 47089808 47249737 47259699
47159681 46799671 46579670 46429676 46239687 46159699
46099718 46269797=20

MOST PROBABLE PEAK TORNADO INTENSITY...120-150 MPH
MOST PROBABLE PEAK WIND GUST...75-90 MPH
MOST PROBABLE PEAK HAIL SIZE...2.00-3.50 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)