Mesoscale Discussion 2413
NWS Storm Prediction Center Norman OK
0131 PM CDT Wed Oct 28 2026
Areas affected...south central through east central Minnesota into
northwestern Wisconsin
Concerning...Severe potential...Watch possible
Valid 281831Z - 282100Z
Probability of Watch Issuance...40 percent
SUMMARY...Increasing thunderstorm development is probable over the
next few hours, accompanied by at least some risk for severe hail.
It is not clear that this will require a severe weather watch in the
near term. However, trends are being monitored for the possibility
of increasing risk for a tornado and/or damaging wind gusts later
this afternoon into early evening near and north/northeast of the
Greater Minneapolis area.
DISCUSSION...Downstream of mid-level troughing overspreading the
Dakotas, lift aided by warm advection in the 850-700 mb layer is
contributing to an ongoing increase in thunderstorm development.
This is occurring coincident with modest destabilization supported
by moistening southerly low-level flow, in the presence of generally
cool thermodynamic profiles. Although initial relatively
warm-layers in mid/upper levels are limiting CAPE, cloud-bearing
layer shear beneath 50-90+ kt southwesterly flow in mid/upper levels
is sufficiently strong to support at least some risk for storms
capable of producing severe hail.
Through 20-22Z, this forcing for ascent, coupled with a band of
trailing strengthening low-level frontogenetic lift, is forecast to
contribute to a further increase in thunderstorm development, which
may gradually begin to consolidate and organize across portions of
southwestern through east central Minnesota. As this occurs, the
extent to which thermodynamic profiles become conducive to more than
an occasional, marginal severe hail threat remains uncertain.
Near-surface thermodynamic profiles are still generally stable to
the north of the Minnesota/Iowa border, and though further low-level
moistening and lift may contribute to saturating profiles
characterized by increasing buoyancy, it is unclear from forecast
soundings whether this will become rooted close to the surface. At
least some recent model output, including convection-allowing
guidance, have been suggesting that convective development may
eventually become coincident with an area of strengthening surface
pressure falls, generally across and north/northeast of the Greater
Minneapolis vicinity by 21-23Z. If this occurs, associated
enlargement of low-level clockwise curved hodographs, convergence
and perhaps near-surface buoyancy could support conditions conducive
to supercells with the potential to produce a tornado or two and/or
damaging wind gusts.
..Kerr/Gleason.. 10/28/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...DLH...MPX...FGF...FSD...ABR...
LAT...LON 46669443 46879215 45779194 44629329 43879544 44959654
46669443
MOST PROBABLE PEAK TORNADO INTENSITY...85-110 MPH
MOST PROBABLE PEAK WIND GUST...UP TO 60 MPH
MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN
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