(CNN) — Severe storms, including possibly tornadoes and hail, are expected to affect wide portions of the United States on Saturday.
“Over 70 million Americans face the threat of severe weather today, with the greatest threat for a significant weather outbreak covering roughly 45,000 square miles, including Chicago metro,” CNN meteorologist Derek Van Dam said.
“All weather modeling points to a significant severe weather outbreak for portions of the Midwest today, with lower chances as you travel south towards the lower Mississippi and Tennessee Valley Region. The threats include tornadoes (a few which may be significant), large to very large hail and severe wind gusts.”
Unseasonably warm and moist air ahead of a rapidly intensifying, low-pressure system will fuel the storms, which will stretch from the central portion of the country to the Great Lakes and Northeast.
The National Weather Service issued a severe thunderstorm watch around 2 p.m. ET for parts of Indiana, Ohio, Pennsylvania and West Virginia until 8 p.m.
CNN meteorologist Dave Hennen said the threat of “long track, violent tornadoes … ramps up significantly Saturday afternoon into Saturday evening.”
Also this weekend, a heat wave in the Southeast is breaking record high temperatures.
Several severe storms are likely to develop, with the highest chance of tornadoes in northern Illinois.
A tweet on Saturday from the weather service’s Storm Prediction Center said some cities at risk of severe storms are Little Rock, Arkansas; Des Moines, Iowa; Louisville, Kentucky; Nashville and Columbus, Tennessee; and Madison Wisconsin.
Here’s the tornado-risk breakdown:
- Northern Illinois: moderate risk
- Missouri, Iowa and Indiana: enhanced risk
- Midwest, Southeast and Ohio Valley: Slight risk
- The weather service warned that the storms may bring damaging winds and large to giant balls of hail.
“As the storm intensifies and heads toward the upper Midwest, a wind-driven cold rain is expected to spread across the central Plains on Saturday,” according to the Weather Prediction Center. “Some of the rain could change over to wet snow Saturday night across the upper Midwest.”
The severe threat will likely peak on Saturday and continue into the early evening.