textproduct: Milwaukee/Sullivan

KEY MESSAGES

- A passing cold front this afternoon may bring some thunderstorms (30 to 50 percent chances), mainly along and southeast of a line from Darlington to Sheboygan. Gusty winds and small hail may occur with the stronger storms, if they develop.

- A Wind Advisory is in effect into the early evening as gusty winds mix down to the surface.

- A Gale Warning remains in effect for the middle third of the open waters of Lake Michigan into late this afternoon, as well as the nearshore waters from Sheboygan to Port Washington.

- Relatively warm and humid conditions with increasing storm chances returns Thursday night into the weekend.

UPDATE

Issued 657 PM CDT Tue May 12 2026

Clearing skies behind this morning's rain allowed for deep mixing to occur late this afternoon. This mixing tapped into a strong jet aloft along and ahead of an approaching front from the northwest. Gusty winds up to 40 knots have been reported over southern WI and a Wind Advisory will remain in effect over southern WI until daytime mixing ceases after sunset.

As of now, the front is roughly located from Sheboygan Co to Rock Co. Spotty showers and a few rumbles of thunder have formed over east central WI. A downward trend in cumulus clouds over southeast Wisconsin suggests that most of the activity along the front will remain confined to areas north of I94 as the front moves east-southeast and clears the area after sunset. Gusty winds will be the main hazard with any showers and storms tonight as the rain will efficiently mix higher winds down to the surface. Otherwise small hail will be a secondary threat with any well established updrafts.

CMiller

SHORT TERM

Issued 118 PM CDT Tue May 12 2026

Tonight through Wednesday night:

Showers along and south of I-94 early this afternoon will wind down by mid-afternoon, with some clearing continuing to work in from the northwest. Given enough afternoon heating, a few thunderstorms may pop along a cold front late afternoon into early evening, mainly along/east of a line from Darlington to Sheboygan. A stronger storm or two is not out of the question given sufficient instability, as there will be plenty of shear to work with. Small hail and gusty winds would be the main concerns.

Skies will clear out for a time behind the front this evening, though cloud are expected to fill in behind the front/low tonight into Wednesday with a cooler airmass in place. Temps will be a bit cooler tomorrow behind the front, but highs will still be within a couple degrees of normal.

DDV

LONG TERM

Issued 118 PM CDT Tue May 12 2026

Thursday through Tuesday:

High pressure will clear skies and light winds on Thursday, with a lake breeze likely late morning into the afternoon. Southerly winds will bring milder conditions to the area, with highs approaching or hitting 70 away from the lake. Cooler conditions are expected near the lake due to the onshore winds for much of the day.

Moisture will increase later Thursday into Thursday night, with a shortwave and area of warm advection aloft expected to bring a round of showers and storms overnight into at least early Friday. Additional shower/storm chances will be possible later Fri into Fri night as another wave rolls through.

Saturday is currently looking mainly dry, as precipitable water values drop to around 0.5" under a weak surface high per the latest ECMWF and GFS deterministic runs. Deeper moisture then makes a quick return Sunday into Monday, with precipitable water values rising to the 1.5-1.7" range. Multiple waves are expected to lift through the area during this period, bringing at least a couple rounds of shower/storm chances. Above normal temps are also expected late weekend into early next week.

DDV

AVIATION

Issued 659 PM CDT Tue May 12 2026

Gusty southwest wind will continue over southeast Wisconsin while gusty northwest winds will continue for KMSN and points westward as a cold front works through the area. The front is projected to clear the area by 03z tonight and all areas in southern WI should feature northwest winds. A few storms will be possible along the front this evening, mainly around KFDL and KSBM. VFR conditions will likely prevail save for any drops in flight category around showers and storms.

SCT to BKN clouds are expected to persist in some capacity overnight. MVFR ceilings may move in around daybreak Wednesday over east central WI for KSBM while areas south toward KMSN, KUES, and KMKE see low VFR ceilings. Gusty northwest winds will persist on Wendnesday amid dry conditions.

CMiller

MARINE

Issued 118 PM CDT Tue May 12 2026

Low pressure of 29.7 inches over northern Wisconsin early this afternoon will reach northern Lake Michigan early this evening and Lake Huron by early Wednesday morning. An associated cold front will approach the lake today, moving through this evening. Gusty south to southwest winds will continue today as the front approaches, with a few gales possible across central and northern portions of the lake through late afternoon. Showers and a few storms will be possible ahead of and along the front today.

Gusty west to northwest winds will arrive behind the cold front tonight into Wednesday. Gusts could approach gale force for a time tonight into early Wednesday, but are expected to mainly stay below gales. Lighter northerly winds are then likely Thursday as high pressure of 30.2 inches moves overhead. Breezy southerly winds are expected to develop Friday ahead of the next approaching low pressure system.

DDV

MKX WATCHES/WARNINGS/ADVISORIES

WI...Wind Advisory...WIZ046-WIZ047-WIZ051-WIZ052-WIZ056-WIZ057- WIZ058-WIZ059-WIZ060-WIZ062-WIZ063-WIZ064-WIZ065-WIZ066- WIZ067-WIZ068-WIZ069-WIZ070-WIZ071-WIZ072 until 8 PM Tuesday.

LM...Gale Warning...LMZ364-LMZ366-LMZ563-LMZ565-LMZ567-LMZ669- LMZ671-LMZ673-LMZ675-LMZ868-LMZ870-LMZ872-LMZ874-LMZ876 until 11 PM Tuesday.

Gale Warning...LMZ643-LMZ644-LMZ645-LMZ646 until 9 PM Tuesday.

Small Craft Advisory...LMZ643-LMZ644-LMZ645-LMZ646 until 4 PM Wednesday.