This article was provided by AccuWeather.com.

Heavy rain from thunderstorms led to severe flooding and numerous road closures late on Tuesday night all across northern Minnesota, including in Duluth, where officials reported 'extensive damage' from the floodwaters early on Wednesday morning.

AccuWeather.com has been warning the Upper Midwest of the risk of flash and urban flooding since early last week.

Both radar estimates and ground observations have indicated more than a half a foot of rain has fallen as of early on Wednesday morning over a large portion of north-central and northeastern Minnesota, with most of the rain falling over the course of just a few hours' time.

Additional thunderstorms expected to bring at least a couple more inches of rain to the region through early tonight will only worsen existing flooding.

Overnight, police in Duluth banned all non-essential travel due to the flooding, which submerged numerous vehicles, leading to water rescues. Some manhole covers were blown off by the pressure of the water in the city, while sinkholes swallowed cars whole.

Mudslides and road collapses were also reported.

In a rare civil emergency bulletin issued overnight, Duluth Police announced that residents in a neighborhood near the Fond du Lac dam were being evacuated. While no threat of a dam failure was imminent, power crews were releasing water to ease the pressure on the structure.

A portion of Interstate 35, Highway 23 and major downtown tunnels remain closed as of early Wednesday morning.

According to the Duluth News Tribune, there were also reports that animals, including a polar bear, escaped from enclosures at the Lake Superior Zoo as floodwaters rose.

Residents and officials are comparing the ongoing situation to flooding that occurred in August 1972 which devastated the city.

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