SPC MD 1391

MD 1391 CONCERNING SEVERE POTENTIAL…SEVERE THUNDERSTORM WATCH LIKELY FOR PORTIONS OF NORTHERN INTO NORTHEAST MINNESOTA AND EXTREME NORTHWESTERN WISCONSIN

Mesoscale Discussion 1391
NWS Storm Prediction Center Norman OK
1047 PM CDT Fri Jun 20 2025

Areas affected...portions of northern into northeast Minnesota and
extreme northwestern Wisconsin

Concerning...Severe potential...Severe Thunderstorm Watch likely 

Valid 210347Z - 210545Z

Probability of Watch Issuance...95 percent

SUMMARY...The severe threat will increase tonight as a bow-echo
merges with supercells and progresses eastward as an organized MCS.
Severe gusts will be the main threat, though some hail and perhaps a
tornado are also possible. A WW issuance will eventually be needed.

DISCUSSION...An intense bow-echo is rapidly propagating
east-northeast across central ND, and will merge with tornadic
supercells across eastern ND over the next couple hours. Afterwards,
an MCS should continue to track eastward over northern MN through
tonight. Though boundary-layer stabilization may gradually limit the
severe nature of the ongoing storms to some degree, current thinking
is that at an appreciable severe wind threat will remain.
Furthermore, any semi-discrete convection that can initiate at the
terminus of the low-level jet, or just ahead of an MCS, may also
pose a large hail threat. Should a bow echo persist, QLCS tornadoes
are also not entirely out of the question, though the tornado
potential is more uncertain given nocturnal stabilization. Either
way, the impending severe threat should warrant the eventual
issuance of a Severe Thunderstorm Watch.

..Squitieri/Smith.. 06/21/2025

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

ATTN...WFO...DLH...FGF...

LAT...LON   48439562 48359355 47919185 47569117 47159103 46699116
            46429160 46409232 46369312 46379389 46429474 46749526
            47239550 48439562 

MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 95 MPH
MOST PROBABLE PEAK WIND GUST...65-80 MPH
MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN

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