Record High Lake Michigan Levels & Lakeshore Flooding

Water Heights Reach Unprecedented Levels On Lake Michigan

NWS Milwaukee, WI

Introduction

When precipitation falls across the Lake Michigan Basin, water follows rivers, creeks, and streams towards Lake Michigan. From 2013 through 2020, this basin has seen above normal annual precipitation, along with record precipitation during 2018 and 2019. The above normal precipitation contributed significantly to the elevated water levels in the Lake Michigan-Huron system. By early 2020 the Lake Michigan-Huron system began to record monthly high lake water levels. These record high water levels continued into late summer of 2020.

Images showing annual precipitation departures from average for Wisconsin between 2013 and 2020. Images courtesy of the Midwest Regional Climate Center

2020 Lake Level Stats

Lake Michigan broke 8 consecutive monthly high water levels from January 2020 through August 2020. These records can be seen on the right. The red line shows the observed lake levels for Lake Michigan-Huron for 2020 exceeding the record high monthly mean lake levels. Both July and August lake water measurements fell just shy of reaching the all-time record. After a quieter summer and fall, water levels dropped 10 inches since their heights point during the summer.

Graphics showing the annual water levels on Lakes Michigan, Huron, and Superior from January through August of 2019/2020.

Vulnerable Shoreline

Record high water levels left the Lake Michigan shoreline, both on the Wisconsin and Michigan sides, extremely vulnerable to lakeshore flooding and shoreline/beach erosion during high wind and large wave events in 2020. Following is a recap of a few of the more significant lakeshore flooding events from 2020.

Image of the Lake Michigan shoreline near downtown Milwaukee.

Notable Events

January 11-12, 2020

As an intensifying surface low tracked just south of Lake Michigan, strong north-northeast winds gusted upwards of 40 to 50 mph along the Lake Michigan shoreline in southern Wisconsin. A few locations saw peak wind gust values approach 50 to 55 mph! These strong winds brought great concern for lakeshore flooding, shoreline erosion and damage as waves were expected to build upwards of 10 to 13 feet. This event was later labeled as an "unprecedented event" based on the impacts.

Port of Milwaukee & Nearby Areas

Animation of surface analyses from the January 11-12, 2020 lakeshore flooding event in southeastern Wisconsin. — Surface analyses from the January 11-12 lakeshore flooding event. Images taken from the Weather Prediction Center surface analysis archive.

Flooding was reported, with nearly 3 feet of water covering roads near the Port of Milwaukee.
Multiple road closures in and around the Port of Milwaukee. After flood waters receded, it was reported that flood waters left behind major potholes in spots. The Port of Milwaukee remained closed for 48 hours during and after the event, reopening on January 13th.
Nearly a foot of ice that had been forming on the lake in early January has been pushed onshore, covering railroad tracks on Jones Island. Additional debris from shoreline damage was also found to be covering these railroad tracks.
Damage to docks at the South Shore Yacht Club, with a section of the local pier to the north destroyed and damage to the break wall.
Large sections of asphalt and/or concrete damage at local boat launches and parks.

Racine Area

Wooden steps at the Wind Point Lighthouse were washed away.
Flooding of parking lots and reports of debris washing onshore at the Racine Yacht Club. Southeast portions of the Yacht Club's property were estimated to lose about 15' of shoreline due to erosion.

April 29-30, 2020

A very slow moving low pressure system tracked over southern Wisconsin and intensified as it passed over the southern half of Lake Michigan. As the system intensified, northeast winds increased over much of Lake Michigan with winds of 40 to 50 mph observed. While impacts were felt along the majority of the Wisconsin shoreline of Lake Michigan during this evening, the City of Green Bay and communities along the Fox and East Rivers saw the most significant impacts.

Animation of surface analyses taken during the April 29-30 event. Images obtained from the Weather Prediction Center surface analysis archive. — Surface analyses taken during the April 29-30 event. Images obtained from the Weather Prediction Center.

Below are some of the impacts from this event:

Walkway and parking lot flooding at South Shore Yacht Club in Milwaukee County. Debris was also thrown into the parking lot.
Strong northeast winds funneling down the Bay of Green Bay caused the Fox and East Rivers in Green Bay to backup into local streets and neighborhoods. Some were evacuated from their homes and numerous roads were closed due to flooding.

Pictures

Photo of break wall damage in the Port Washington harbor. — Collection of photos captured by area emergency managers during the lakeshore flooding events of 2020. From left to right: break wall damage at the Port Washington harbor, break wall damage near the Port of Milwaukee, and left over debris following a lakeshore flooding event in Racine County.

Photo of break wall damage near the Port of Milwaukee harbor. — Collection of photos captured by area emergency managers during the lakeshore flooding events of 2020. From left to right: break wall damage at the Port Washington harbor, break wall damage near the Port of Milwaukee, and left over debris following a lakeshore flooding event in Racine County.