textproduct: Milwaukee/Sullivan

KEY MESSAGES

- A round or two of severe storms are expected from mid afternoon into the early evening. Significant severe storms are possible during this time. Isolated tornadoes, damaging winds, and large hail are the main concerns. There is a small potential for flash flooding especially in urban areas.

SHORT TERM

Issued 1256 AM CDT Wed Jun 10 2026

Today and tonight:

The thunderstorm east of Monroe will drift into IL early this morning with only slight chances for redevelopment through 08-09Z. Although the cold front will continue to dissipate west of the MS River, drier air at 925-850 mb on wly winds will contribute to the ending of the showers and storms early this morning. Areas of light fog and low stratus may form early this morning given the moist conditions and weakening sfc winds.

The potential for significant severe thunderstorms still looks fairly probable today as low pressure and a vorticity maximum tracks newd from KS this morning reaching ne IA by 18Z then into east central WI by 00Z Fri. A strong sswly low level jet of 50 kt will quickly surge nwd ahead of the low bringing a round of low to mid level warm, moist advection and showers and storms to srn WI from late morning into the early afternoon. These storms will likely be elevated with the potential for large hail. As the sfc low tracks from ne IA to east central WI accompanied by the trailing cold front, high thetae air will surge north across srn WI with a MLCAPE gradient from 1000-1500 J/KG over central WI to 2500-3000 J/KG toward the IL border. Strong deep layer and low level shear will be in place as shown by large, curved hodographs. CAMs are not surprisingly highlighting supercells via updraft helicity, but also line segments with a QLCS as the predominant mode. Isolated tornadoes, damaging winds, and large hail are all probable including some significant occurrences of each possible.

Wly winds and cold advection will then prevail in the wake of the storms this evening. Temps are expected to drop into the 50s by sunrise Fri.

Gehring

LONG TERM

Issued 1256 AM CDT Wed Jun 10 2026

Friday through Wednesday:

Light to modest wly surface winds, dry weather, and near normal temps will return for Friday in the wake of a cold front Thu nt. Otherwise zonal flow will prevail into the weekend. A weak trough in the low to mid levels will approach from the west Sat afternoon and pass Sat nt. Weak low to mid level warm, moist advection, but slightly stronger frontogenesis in that layer will support 60-80 percent chances of showers and thunderstorms.

A larger scale upper trough will then become established over Ontario early next week including weak shortwave troughs rotating across the region. This will bring below normal temps to srn WI, and shower chances of 20-40 percent at times through Wed.

Gehring

AVIATION

Issued 1256 AM CDT Wed Jun 10 2026

Areas of MVFR Cigs and Vsbys (due to BR) are expected to develop early this morning then dissipate shortly after sunrise. Although, areas of MVFR Cigs will remain possible through the day into the early evening due to a moist and unstable airmass and numerous showers and storms. Breezy sly winds will develop this afternoon then shift wly with a cold frontal passage from late afternoon into the evening.

Gehring

MARINE

Issued 1256 AM CDT Wed Jun 10 2026

Areas of dense fog will remain possible today due to a moist flow over the relatively cold waters of the lake. Otherwise modest south to southwest winds can be expected this morning but will become breezy south to southeasterly this afternoon. This will occur as low pressure around 29.5 inches moves from eastern Iowa to central Lake Michigan by early this evening, then northeast into Ontario by early Friday morning. Winds will become westerly and breezy behind the low pressure area this evening into the overnight. Modest to breezy southwest winds will follow for Friday into Saturday. Numerous thunderstorms are expected this afternoon and evening and may become severe.

A Small Craft Advisory may be needed from Sheboygan to Winthrop Harbor late this afternoon and into the late night as breezy south winds develop ahead of a cold front then shift wly with the frontal passage. Waves of 3 to 5 feet are expected north of North Point Lighthouse.

Gehring

MKX WATCHES/WARNINGS/ADVISORIES

WI...None. LM...None.