(CNN) — Severe weather, including tornadoes and hail, was possible Saturday afternoon and night for large portions of the United States, especially the Midwest.
The National Weather Service’s Storm Prediction Center issued a rare “Particularly Dangerous Situation” tornado watch for parts of the Midwest through Saturday night. These storms could produce hail the size of baseballs or larger, along with damaging 70-plus mph winds.
The states most at risk are Iowa, Missouri and Illinois. That’s where long-track, intense and multiple tornadoes could develop during the afternoon and continue into the evening.
Overall, 70 million Americans face the threat of severe weather, CNN meteorologist Derek Van Dam said. The greatest threat for a significant weather outbreak covers roughly 45,000 square miles, including the Chicago metro area.
“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,” he said
“The threats include tornadoes (a few which may be significant), large to very large hail and severe wind gusts.”
The weather service issued the first of several tornado watches for parts of Iowa, Illinois and Missouri Saturday afternoon and more serious tornado warning for Stuart and other towns west of Des Moines.
In a tweet, the weather service reported a funnel cloud with a brief tornado touchdown 6 miles southeast of Fontanelle moving northeast. No other details were available.
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.
A tweet on Saturday from the weather service 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
“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.
Also this weekend, a heatwave in the Southeast is breaking record high temperatures.