Day 1 Convective Outlook  
NWS Storm Prediction Center Norman OK
1240 AM CDT Sun Jun 16 2024

Valid 161200Z - 171200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF
THE NORTHERN/CENTRAL PLAINS INTO THE UPPER GREAT LAKES...

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

...Northern/Central Plains to the upper Great Lakes...

Northern Rockies short-wave trough will eject northeast across SK/MB
into western ON by 17/00z. This feature is expected to partially
influence the upper Great Lakes region, with only weak height falls
glancing northern portions of MN. Otherwise, the primary concern for
the upper Great Lakes will be the early-day short-wave trough that
will eject across WI/MI. This feature is currently located over
western IA but convection has weakened considerably despite the
large-scale support. Current thinking is non-severe convection
should spread northeast across WI into the U.P. of MI early within a
warm advection corridor.

Weak short-wave ridging will be noted across much of the upper MS
Valley in the wake of the early-day feature. The boundary that
surges across MN, arcing back into the central Plains will provide a
focus for low-level convergence; however, boundary-layer heating may
be inadequate for appreciable surface-based convection until late in
the day. Latest models are not aggressive in developing convection
along the boundary, but rather generate elevated convection north of
the wind shift later in the evening as the LLJ refocuses over the
central Plains after sunset. A strong signal for robust elevated
convection exists across portions of SD/NE during the latter half of
the period, and this activity should spread northeast during the
overnight hours. Forecast soundings exhibit substantial MUCAPE (in
excess of 2000 J/kg), if lifting parcels above 850mb within the
strengthening warm-advection zone. Hail should be the primary
concern with the elevated convection.

..Darrow/Thornton.. 06/16/2024

Read more

Day 2 Convective Outlook  
NWS Storm Prediction Center Norman OK
1243 AM CDT Sun Jun 16 2024

Valid 171200Z - 181200Z

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

...SUMMARY...
Scattered strong to severe storms will be possible Monday over much
of the northern Plains toward the upper Mississippi Valley.

...Synopsis...
On Monday, strong southwest flow aloft will extend from the Great
Basin into the northern Plains and upper MS Valley, with an early
lead wave over MN and the primary trough over the Pacific Northwest.
Height rises will occur over much of the northern Plains during the
day, before cooling aloft spreads east across the northern Rockies
and High Plains late. Meanwhile, an upper ridge will remain over the
East.

At the surface, low pressure will form over WY and CO, with a warm
front from NE into southern MN and northern WI by 00Z. South of this
front, mid to upper 60s F dewpoints will be common. Overnight, a
cold front will push east across the Dakotas and toward central NE,
as warming continues north across the upper MS Valley. The surface
low will translate northeast from CO toward ND by 12Z Tue.

...Northern Plains and upper MS Valley...
Early day storms and rain are expected from eastern SD across MN and
into northern WI and upper MI, with a gradual decrease in coverage
throughout the day. This activity will be well north of the warm
front, and rain cooled air could reinforce the boundary for much of
the day.

By late afternoon, an unstable air mass along and south of this
front may lead to renewed development, and a few storms could
produce gusty winds or marginal hail. Additional storms are likely
down the dryline into southwest NE into western KS where low-level
lapse rates will be steep. Locally large hail or strong winds will
be possible.

During the evening and overnight, a greater threat of strong to
severe storms may materialize as the warm front surges north along
with southerly 850 mb winds increasing to 60 kt over a broad area.
In addition the low-level moisture flux, the surging cold front will
add lift, with the end result areas of storms capable of hail and
locally damaging gusts. A greater severe risk than forecast for
damaging winds may exist along the boundary, especially if it moves
farther north than forecast with earlier air mass recovery.

..Jewell.. 06/16/2024

Read more