More than 35 million Americans from Wisconsin to Oklahoma are at risk of a severe weather outbreak on Friday, including tornadoes, as some violent storms have already fired up across multiple states.

So far, there have been 12 reported tornadoes across five states and a confirmed tornado on the ground in Illinois on Friday.

The greatest risk for strong tornadoes is in central and southern Wisconsin through eastern Iowa. The northern halves of Illinois and Missouri have the greatest risk for destructive winds.  

A tornado watch is in effect for parts of Wisconsin, Minnesota, Iowa, and Illinois — including Madison, Milwaukee, Des Moines and Davenport — through 8 p.m. CT. Intense tornadoes are possible, as well as large hail up to 3.5″ in diameter and damaging gusts to 70 mph.

Tornado watches are also in effect for parts of Kansas, Oklahoma and Missouri — including Kansas City, St. Louis and Chicago — through 11 p.m. CT. Some intense tornadoes, significant wind gusts to 75 mph and scattered large hail are all possible.

As storms develop Friday afternoon, there is a chance for discrete supercells with very large hail, strong tornadoes and destructive, straight-line winds. 

The National Weather Service on Friday upgraded the severe weather potential for parts of the Heartland. The agency’s Storm Prediction Center added a level 4 of 5 “moderate risk” for parts of northwest Oklahoma, central and eastern Kansas and west-central Missouri. This includes Kansas City, Missouri, and Wichita and Topeka, Kansas.

Thunderstorms expected to fire up later Friday afternoon into the evening in this area have the potential to produce damaging hail greater than baseball-size, very strong and destructive wind gusts of up to 90 mph and some tornadoes.

Flash flooding is also possible, with flood watches issued from Missouri to northern Michigan.

The severe weather outbreak comes after flooding and tornadoes already impacted parts of the region this week.

The NWS confirmed at least 28 tornadoes across nine states stretching from California to New York this week, with Wisconsin, Iowa and Illinois hardest-hit.

These storms will bring additional rain to parts of Wisconsin and Michigan, which saw widespread flooding, prompting states of emergency. The states could see an additional 1 to 3 inches of rain on top of their extremely saturated soil, expanding river flooding and the risk of sinkholes. 

A 41-year-old man was killed by a lightning strike Wednesday evening in a parking lot in Waukesha County, Wisconsin, authorities said.