Millions of Americans are under a tornado watch Thursday as powerful storms sweep across parts of the Midwest. The National Weather Service (NWS) said the alert covers dozens of counties in Illinois, Iowa and Missouri until 3pm CT (4pm ET). The Chicago area is at the heart of the threat, with meteorologists warning that tornadoes remain relatively rare in the region despite an increase in severe weather outbreaks in recent years. AccuWeather Expert Meteorologist Brandon Buckingham said: 'All of the ingredients required for severe thunderstorms will be in place across the Plains and Midwest for a severe weather outbreak [through] Thursday.' Buckingham warned that abundant moisture, an unstable atmosphere and powerful storm systems moving out of the Rockies are expected to fuel widespread thunderstorms across the region. The storms could unleash wind gusts approaching 100 mph, softball-sized hail and dozens of tornadoes, potentially generating hundreds of severe weather reports across the Plains and Midwest.

AccuWeather is urging locals to have a tornado plan ready and 'identify safe interior areas like a bathroom or basement. Seek the lowest floor possible within a sturdy building and away from windows.' 'Keep an emergency kit and sturdy shoes accessible to help you safely navigate debris and potential power outages after the storm,' meteorologists added. AccuWeather meteorologists emphasized the high risk of severe thunderstorms for a heavily populated area of the Midwest, including Chicago, Rockford and Peoria, Illinois; Milwaukee and Madison, Wisconsin; Grand Rapids and Kalamazoo, Michigan; Burlington, Dubuque and Davenport, Iowa and South Bend, Indiana. Widespread severe weather is expected in this zone, they said in a statement. 'Those outdoors should be prepared to take shelter in an enclosed building and avoid lingering beneath a canopy of trees, as high winds could bring them down without notice, AccuWeather said. The powerful storms could also spark power outages throughout the area.

While the tornado watch is only in place for three states, a severe weather risk looms over nearly 50 million people from southern Canada to Texas to Michigan and Ontario. A storm is also heading to the East, which meteorologists warned could trigger a number of flight delays and cancellations. 'Torrential downpours may not only reduce the visibility for highway motorists, but they can also lead to flash urban flooding that can swamp vehicles in a matter of minutes,' said AccuWeather. Thunderstorms are expected Thursday and Friday in parts of North Carolina, New York state and a portion of New England. 'There will be a pocket both days where a greater concentration of severe weather is likely, mainly from northern Virginia to southeastern New York and southwestern New England,' AccuWeather explained.

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