ACUS01 KWNS 101255

SWODY1

SPC AC 101254



Day 1 Convective Outlook  

NWS Storm Prediction Center Norman OK

0754 AM CDT Wed Jun 10 2026



Valid 101300Z - 111200Z



...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF

THE UPPER MISSISSIPPI VALLEY AND MIDWEST...



...SUMMARY...

Scattered to numerous severe thunderstorms with potential for large

hail in excess of two inches in diameter, a few strong tornadoes and

damaging winds with gusts over 75 mph are expected this afternoon

and evening across parts of the Upper Mississippi Valley and

Midwest.



...Midwest/Missouri Valley and Upper Mississippi Valley...

With a broad upper trough centered near/east of the northern CONUS

and Canadian Rockies, its lead portion will shift northeastward over

the Upper Midwest/Lake Superior vicinity today, with more limited

forcing for ascent and height falls farther south, until the

late-night arrival of a secondary portion of this trough out of the

northern Rockies and north-central High Plains. The primary synoptic

low/surface triple point will shift from northern Minnesota

north-northeastward into Canada. A moist environment will be in

place to the east of an eastward-advancing cold front, with

north-northeastward air mass recovery in the wake of overnight/early

morning storms (MCS) across the eastern Dakotas and

Minnesota/Wisconsin.



Showers and thunderstorms have increased in the predawn hours across

eastern portions of Nebraska/Kansas into northwest Missouri and

western Iowa. This development is driven by a strong southwesterly

low-level jet and ample elevated moisture transport. For additional

short-term details, see Mesoscale Discussion 1063. This development

could further increase today and shift east-northeastward across

Iowa/northern Missouri and eventually northwest Illinois today,

complexifying the forecast scenario. These storms could pose a

severe-storm risk within this corridor relatively early today, with

subsequent development expected by late afternoon near the cold

front spanning Minnesota into east-central Iowa, northern Missouri

and eastern Kansas. The early day storms, pending how extensive they

are, could spatially influence via outflow/cloud debris a preferred

zone for redevelopment near the Iowa/Missouri border vicinity toward

west-central/northwest Illinois. Meanwhile, farther north, in closer

proximity to the large-scale height falls, another preferred zone of

severe-storm development could focus across northern/eastern

Minnesota into western Wisconsin.



Deep-layer shear will be strengthening across these regions and will

broadly support initial supercells capable of large hail, with very

large hailstones possible with initial development near the cold

front late this afternoon and early evening. A predominant large

hail risk is also expected late tonight with anticipated mostly

elevated development across central/eastern Nebraska and northeast

Kansas, attributable to the approaching upstream system and an

re-intensifying low-level jet and warm/moist advection. Large hail

aside, tornadoes will be possible regionally late this afternoon and

evening, a few of which could be strong (EF2+). The early day storms

could ultimately organize and pose a damaging wind threat, and more

broadly so this evening as storms trend upscale near/east of the

cold front, potentially leading to a multi-round severe potential in

some areas today and tonight.



...Ohio Valley/Central Appalachians/Mid-Atlantic States...

A moist and unstable airmass will be in place today across much of

the region, with surface dewpoints generally in the lower 70s F.

While some thunderstorms are ongoing early today, additional and

more potent thunderstorm development is expected into the afternoon

as the boundary layer destabilizes. This development will be further

influenced by one or more weak eastward-moving MCVs over the upper

Ohio River Valley this morning. Damaging winds will be the primary

hazard regionally.



..Guyer/Wendt.. 06/10/2026



$$