Mesoscale Discussion 1413
NWS Storm Prediction Center Norman OK
0659 AM CDT Wed Jul 01 2026

Areas affected...Southeast MN and extreme northeast IA into
central/southern WI

Concerning...Severe potential...Watch possible 

Valid 011159Z - 011430Z

Probability of Watch Issuance...40 percent

SUMMARY...Strong to locally severe storms are possible through the
morning.

DISCUSSION...At 1155 UTC, a small, forward-propagating storm cluster
is moving across central WI. This cluster is moving through an axis
of rich boundary-layer moisture, with mid 70s F dewpoints supporting
MLCAPE of greater than 2000 J/kg, per recent objective mesoanalyses.
30-40 kt is sufficient for continued storm organization, and this
cluster will continue to pose a short-term threat of at least
locally damaging wind. Early visible imagery depicts relatively
clear skies and some potential for diurnal heating across eastern WI
in advance of this cluster. As a result, this cluster may persist
through the morning and eventually approach Lake Michigan, though
its longevity remains somewhat uncertain due to generally modest
large-scale ascent. 

Farther west, extensive convection is ongoing within a
warm-advection regime across southern MN. Occasionally organized
storms may continue to develop within this regime, and pose a
short-term threat for isolated hail and damaging wind. Farther west,
multiple MCVs are noted from northern NE into northeast SD.
Increasing flow in the 700-500 mb layer (as depicted in short-term
guidance) associated with these MCVs may allow for some uptick in
storm organization and longevity later this morning, near and just
north of an outflow-influenced front draped from southern MN into
central WI. 

While timing of a more substantial severe threat remains uncertain,
watch issuance is possible later this morning if trends support an
increasing coverage and duration of organized storms.

..Dean/Smith.. 07/01/2026

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

ATTN...WFO...GRB...MKX...ARX...MPX...DMX...

LAT...LON   43809382 44369391 44809234 44969153 45008947 44898793
            44808737 44578735 44208748 43788768 43538780 43228790
            43139019 43169168 43349314 43439364 43809382 

MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 90 MPH
MOST PROBABLE PEAK WIND GUST...55-70 MPH
MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN

Day 4-8 Convective Outlook  
NWS Storm Prediction Center Norman OK
0400 AM CDT Wed Jul 01 2026

Valid 041200Z - 091200Z

...DISCUSSION...
Flow aloft will become more zonal by this weekend as the upper-level
ridge flattens and begins to shift/build westward. The strongest
mid-level winds will be present across the northern tier of the
CONUS. An upper-level low in the vicinity of the Canadian Maritimes
will bring a belt of stronger mid-level winds across the Northeast.
Some southward movement of a surface boundary can be expected within
the Great Lakes/Ohio Valley/Mid-Atlantic this weekend into early
next week. At the same time, northwesterly flow aloft will develop
over the High Plains along with moisture pushing farther northwest
into the region.

Severe potential will largely be driven by mesoscale features such
as localized convergence along stalled/weak boundaries as well as
MCVs from prior convection. The airmass across much of the Plains
into the Southeast and Mid-Atlantic will be quite unstable and
strong heating will occur underneath the increasingly muted upper
ridge. Subtle lift from shortwave troughs may promote greater
convective coverage in parts of the Mid-Atlantic early next week.
However, the stronger, but still modest, shear will be displaced
from the most buoyant airmass. Additional convection will be
possible along the surface boundary within the Midwest/Ohio Valley,
but shear will generally be weak. More organized convection may also
develop within the northwest flow pattern in the High Plains, but
predictability remains low as to where this will eventually occur.