Nearly the entire state of Wisconsin is under the threat of severe storms Monday evening, bringing the possibility of tornadoes and severe hail.

A line of severe storms is expected to move into western Wisconsin and sweep across the state between 6 p.m. and midnight. 

Much of the western region, from Polk County into northern Grant County, and part of central Wisconsin are under a “moderate risk” designation, or a four on the five-level scale used by the National Weather Service’s Storm Prediction Center. 

“Rather than just a few severe weather reports, they are actually looking for the potential of numerous severe weather reports,” said Cathy Zapotocny, lead meteorologist for the NWS La Crosse office.

She said the elevated rating also means a higher probability of hail, damaging wind and stronger tornadoes.

While several rounds of storms are expected to make their way through the state Monday, Zapotocny said the line of storms forecast in the evening has many of the “ingredients” needed to develop severe threats.

“They’ve got the instability. They’ve got the strong [wind] shear, and they’ve got the organization,” she said.

Zapotocny said it is rare to see the national prediction center predict a moderate risk storm so far in advance. The rating was upgraded on Saturday, making it only the third time on record that a level 4 storm was forecast three days in advance.

Zapotocny urged residents to be extra vigilant about tornado watches and warnings issued at night, when the darkness can make it more difficult to spot a tornado embedded in a storm.

“Just being aware of the weather can really go a long way,” she said. “When you are hearing the thunder, take shelter and just look out for each other when these situations arise. Sometimes it just takes one person to let people know about a storm coming their way.”

She said people and animals should shelter in a sturdy location, preferably one with concrete between themselves and outdoors. She encouraged residents to park vehicles in a garage overnight, or at least away from trees that could be toppled by strong winds.

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