909
ACUS02 KWNS 150523
SWODY2
SPC AC 150522

Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1222 AM CDT Sat Jun 15 2024

Valid 161200Z - 171200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE
NORTHERN PLAINS AND UPPER MISSISSIPPI VALLEY LATE ON SUNDAY AND
SUNDAY NIGHT...

...SUMMARY...
Scattered strong to severe storms are expected Sunday evening and
overnight from parts of the northern Plains into the upper
Mississippi Valley, with hail the primary risk.

...Synopsis...
On Sunday, an upper trough will move east/northeast across MT and
the far northern Plains, becoming negatively tilted as the parent
low moves into MB. Meanwhile, a lead wave will move quickly east
across the Great Lakes region around the north side of a strong
upper ridge. Late in the period, height falls will again increase
across the Pacific NW into the Rockies as another trough amplifies
there.

At the surface, a nearly stationary front will extend roughly from
northeast CO into southern MN, with a weak lee trough from eastern
CO into NM. A prominent surface ridge will extend from the high
pressure center over the Mid Atlantic southwestward toward the Gulf
Coast.

A broad area of southwest winds around 850 mb will maintain a warm
low-level air mass south of the stationary front across the Plains
and around the upper ridge as warmer air spreads east across the
Great Lakes. The presence of a moist and unstable air mass in the
vicinity of the stationary front should be the primary focus for
scattered storms, some severe, late in the day and overnight from
eastern WY toward MN and WI.

...WI into MI Early...then WY to WI Late...
Rain and storms are likely to be ongoing Sunday morning over WI, in
a region of low-level warm advection, and where elevated instability
will be substantial. This activity will progress quickly east toward
Upper MI and perhaps northern Lower MI, with a general weakening
trend. However, marginal hail cannot be ruled out especially early
in the day.

Behind this wave of activity, strong instability will develop.
However, lift will be quite weak as temporary height rises occur.
Still, a weak surface boundary along with peak heating could
initiate isolated cells capable of hail from MN into WI during the
late afternoon.

More likely, most of the activity will hold off until after 00Z, as
elevated instability builds back north. Between 03-06Z, scattered
storms will be likely from eastern WY across parts of NE and SD,
southern MN, northern WI and into western Upper MI. Vigorous
convection will likely produce large hail at times, with favorable
mid and high level flow elongating hodographs despite the main wave
well north of the region.

Elsewhere, more isolated storms will be possible extending south
along the dryline from southwest NE into western KS and far eastern
NM. Locally strong gusts and brief hail may occur, but shear will be
weak.

..Jewell.. 06/15/2024

$$