234
ACUS02 KWNS 030532
SWODY2
SPC AC 030530

Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1230 AM CDT Wed Jun 03 2026

Valid 041200Z - 051200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM PARTS OF THE
NORTHERN HIGH PLAINS ACROSS SOUTH DAKOTA AND NORTHERN NEBRASKA INTO
SOUTHWEST MINNESOTA...

...SUMMARY...
Severe thunderstorms capable of large to very hail and damaging
winds are possible from parts of the northern High Plains into lower
elevations of the northern and central Plains Thursday afternoon
into night. More isolated occurrences of large hail and damaging
winds appear possible in parts of the upper Midwest and upper Great
Lakes.

...Synopsis...

A low-amplitude, cyclonic flow regime will be maintained across the
north-central U.S. with several embedded disturbances moving through
that airflow pattern. At the surface, a cold front is forecast to
move from the upper MS Valley into the upper Great Lakes with that
boundary trailing southwest through the mid MO Valley to eastern WY,
where it will link with a lee cyclone. A dryline/lee trough will
extend south from the low pressure through the central and southern
High Plains.


...Northern and Central Plains...

A short-wave trough embedded in the cyclonic flow initially over the
northern Rockies Thursday morning will shift into the northern High
Plains by afternoon. Strengthening mid-level winds and forcing for
ascent downstream from that feature will progressively overspread a
moist and moderately unstable (MLCAPE 1000-1500 J/kg) upslope regime
present across portions of southeast MT, northeast WY, and western
SD, to the north of the surface boundary. Those processes will
contribute to initial storm development in those areas by mid
afternoon with the kinematic environment favoring supercells capable
of large to very large hail and perhaps a tornado or two.

Additional storm development will be possible farther east along the
front in central/eastern SD and northern NE amidst a moderately
unstable environment (MLCAPE of 1500-2000 J/kg) with weakening
vertical shear and mid-level lapse rates with eastward extent. As
such, a mix of multi-cell and some supercell structures appear
possible with an associated risk for large hail and severe wind
gusts.

Those two separate regimes may consolidate into one or more MCSs
Thursday evening/night, with a continued risk for damaging winds and
sporadic large hail.

Elsewhere, diurnally enhanced storms will be possible south along
the lee trough into northeast CO, as well as ahead of a sheared
vorticity maximum moving through portions of northeast KS, eastern
NE, and IA. Steep lapse rates and around 30 kt of deep-layer shear
may support isolated, high-based storms in the former area with some
wind and hail threat. Poorer mid-level lapse rates and weaker
vertical shear expected in the latter areas would limit
severe-weather potential to mainly wet microburst activity. Model
soundings do show some low-level hodograph curvature, so a brief
tornado cannot be ruled out.

...Upper Midwest/Upper Great Lakes...

Relatively poor mid-level lapse rates are forecast across the
pre-frontal warm sector Thursday; however the presence of
boundary-layer dewpoints in the low to mid 60s will largely
contribute to a narrow axis of MLCAPE up to 1000-1500 J/kg by
afternoon. The glancing influence of a mid-level low moving into the
northwest Ontario coupled with convergence along the front are
expected to foster widely scattered thunderstorms by mid to late
afternoon.

The presence of 30-40 kt of deep-layer shear will be sufficient for
multi-cells and transient supercell structures capable of locally
damaging wind gusts and perhaps marginally severe hail. Modest
strengthening of the low-level jet is noted across northern WI into
the western UP of MI late Thursday afternoon into evening, which
could yield sufficient low-level shear for some tornado risk. No
probabilities will be included in this forecast due to uncertainty
in the degree of instability in those areas.

..Mead.. 06/03/2026

$$