A strong, slow-moving low pressure system drifted southeast across the upper Midwest over a 3 day period from May 17 through May 19. This system interacted with copious moisture streaming north from the Gulf of Mexico that resulted in several rounds of moderate to heavy rainfall across Wisconsin, northern Illinois and Lower Michigan. Widespread rainfall amounts of 3 to 5 inches fell across much of east-central and northeast Wisconsin with a few locations breaking daily rainfall totals. The heavy rainfall was also accompanied by strong northeast winds gusting to 40 to 50 mph. The combination of heavy rainfall, record high Lake Michigan water levels and northeast winds, led to widespread flooding and beach erosion at shoreline areas along the Bay of Green Bay and Lake Michigan. The strong northeast winds hindered the drainage of water from the Fox and East Rivers into the mouth of the bay, which contributed to flooding in parts of downtown Green Bay and further inland along the East River. Significant flooding was also observed in the city of Oconto along the Oconto River.

Lakeshore Flood in BROWN, WISCONSIN
From 17-MAY-20 23:00:00 to 19-MAY-20 19:00:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

The combination of record high lake levels on the Bay of Green Bay, 3 to 5 inches of rainfall, and strong northeast winds caused flooding along the shoreline in Brown County. Numerous streets were closed along the Bay of Green Bay due to the high water.

Lakeshore Flood in SOUTHERN OCONTO, WISCONSIN
From 17-MAY-20 19:00:00 to 19-MAY-20 19:00:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: County Official

The combination of record high lake levels on the Bay of Green Bay, 3 to 5 inches of rainfall, and strong northeast winds caused flooding along the shoreline in Oconto County.  The high water damaged Bayshore Road in the city of Oconto.

Lakeshore Flood in SOUTHERN MARINETTE, WISCONSIN
From 17-MAY-20 19:00:00 to 19-MAY-20 19:00:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: County Official

The combination of record high lake levels on the Bay of Green Bay, 3 to 5 inches of rainfall, and strong northeast winds caused flooding along the shoreline in Marinette County. The high water flooded Red Arrow Park.

Lakeshore Flood in DOOR, WISCONSIN
From 17-MAY-20 23:00:00 to 19-MAY-20 19:00:00 (CST-6)
Property damage: 30.00K
Crop damage: 0.00K
Reported by: Emergency Manager

The combination of record high lake levels on the Bay of Green Bay, 3 to 5 inches of rainfall, and Lake Michigan along with strong northeast winds caused flooding along the shoreline in Door County.  The high water damaged South Lake Michigan Drive in the town of Clay Banks and Bayshore Road in the town of Union.

Flood in BROWN, WISCONSIN
From 18-MAY-20 02:00:00 to 19-MAY-20 17:00:00 (CST-6)
Location: CORMIER
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

The combination of record high lake levels on the Bay of Green Bay, 3 to 5 inches of rainfall, and strong northeast winds backed up the waters on the Fox and East Rivers in Green Bay as well as Duck Creek in the village of Howard. Several streets were closed due to flooding along the Fox and East River in Green Bay as well as Duck Creek in the village of Howard.