Marine Weather and Tide Forecast for Sturtevant, WI

UPDATE
Issued 643 AM CDT Mon May 18 2026

A few thunderstorms have popped up this morning over south central to southeast Wisconsin, riding some of the better low to mid level warm advection from an LLJ into the area. These storms should be fairly pulse like, having quick spikes in intensity, following by core collapses. Sub-severe hail and gusty winds, as well as lightning will be the main hazards.

CMiller

SHORT TERM
Issued 1200 AM CDT Mon May 18 2026

Today through Tuesday:

The nrn portion of the QLCS over ne IA and se MN has recently produced severe wind gusts but gradual weakening is expected as it moves into greater CIN. Farther to the south, the gust front is outrunning the convection but sporadic wind gusts of 40-50 mph are still occurring. For srn WI, gusty winds and scattered storms will continue to initiate along and behind the gust front during the early morning hours. MUCAPE of 1500-2000 J/KG will be present but with high LFCs at 650-700 mb. The high LFCs should aid in the further dissipation of the organized line and/or transitioning to elevated scattered storms.

During this time, a wave of low pressure will track across MN to wrn Lake Superior and be the catalyst to shifting the warm front nwd into central WI. Thus the low stratus and areas of fog toward central WI will come to an end during the early morning hours. Some showers and storms will likely linger through later this morning, but capping will set in again and will aid in some scattering of clouds and temps nearing 80F for the afternoon.

Another wave of low pressure will develop from the central Great Plains to nrn WI from late Mon afternoon until 12Z Tue, while the main shortwave trough tracks from the central Rockies to nw WI. The actual trailing cold front will likely not pass until Tue, but there is some confidence in another round of showers and storms for mainly after midnight (early Tue AM) as another MCS moves into srn WI from the west. The MCS may already have reached the dissipating stage at this time, but there is uncertainty with the timing of the evolution. Once again, damaging wind gusts would be the main concern. Finally, there may be some shower and storm development with the cold frontal passage Tue afternoon with severe probs are low at this time.

Gehring

LONG TERM
Issued 1200 AM CDT Mon May 18 2026

Tuesday night through Sunday:

Gusty northwest winds remain in place through Tuesday night as high pressure builds in from the northwest. Winds gradually diminish into Wednesday as high pressure settles into the region.
Temperatures are expected to be back into the 60s and low 70s for highs and lows in the upper 30s to mid 40s through midweek. High pressure remains dominant through Thursday before propagating eastward into the Northeast U.S. Low pressure will begin to deepen in the lee of the Colorado Rockies, ejecting into the Plains Friday morning. With high pressure remaining over the Northeast, models are indicating a split low progression, with one portion of upper level energy propagating through the Lower Mississippi Valley along a Gulf humidity axis, and the other portion following the long wave pattern northeastward into the western Great Lakes.
A few showers and thunderstorms may work their way in as early as Thursday night into Friday (15-25%), with more potential for widespread showers and thunderstorms into Friday night and Saturday as the cold front from the Midwest low phases with the southern low. Confidence in timing and placement remains in question due to model discrepancies, so maintained NBM probabilities for this update. Precipitation exits Saturday night as ridging begins to build back into the southern Wisconsin from the central Plains. Expect temperatures to return to the upper 70s and low 80s Sunday as winds shift to southerly, with additional chances for storms Sunday night into Monday.

MH

AVIATION
Issued 645 AM CDT Mon May 18 2026

Mostly VFR conditions are expected today save for drops in flight category with any showers and storms. There is some potential for fog for lakeshore terminals this afternoon. Winds will be out of the south southwest and breezy. Tonight ceilings lower to MVFR and potentially IFR as a line of thunderstorms moves through from the west.

CMiller

MARINE
Issued 1200 AM CDT Mon May 18 2026

A warm front will move from southern Lake Michigan to northern Lake Michigan this morning. East to northeast winds will become breezy out of the south. Areas of dense fog may occur at times until the front passes. Breezy south winds will then continue through today into Tuesday followed by a wind shift to the northwest late Tuesday afternoon and evening with the passage of a cold front. High pressure and light and variable winds will then take hold from late Wednesday into Thursday.

A Marine Dense Fog Advisory is in effect from Sheboygan to North Point Lighthouse until 3 AM CDT today. The fog will dissipate once the warm front moves to the north, and south winds and milder temperatures arrive.

Gehring

MKX WATCHES/WARNINGS/ADVISORIES
WI...None.
LM
Small Craft Advisory
LMZ643 until 7 PM Tuesday.

Small Craft Advisory...LMZ644-LMZ645-LMZ646...4 AM Tuesday to 4 PM Tuesday.