Unseasonable warmth is setting the stage for damaging thunderstorms capable of bringing powerful wind, large hail and tornadoes to nearly 175 million people in the central and eastern United States Sunday and Monday.

March has already dealt a slew of potent storms and tallied up more tornado reports than as of the same time last year. Some of the same areas hit hard by a deadly storm two weeks ago could end up in the path of the next round of thunderstorms. While this weekend’s forecast doesn’t look to be as extreme, danger could ramp up quickly and there are millions of people potentially in harm’s way.

The weekend will start off feeling more like late May or early June from the Plains to the East Coast before a wide-reaching storm and potent cold front develop in the central US and race east.

A few severe thunderstorms with damaging winds and hail are possible Saturday night, mainly from Kansas and Missouri to Iowa, as the storm starts to form. But a much more widespread and dangerous severe weather threat will develop on Sunday once the storm hits full strength.

Here’s what to expect this weekend and early next week.

Strong, long-lived tornadoes possible Sunday

A cold front stretching from the Midwest to the southern Plains on Sunday will erase any late-springlike heat that built up over the eastern half of the country. Chilly air behind this front will clash with warm, moist air ahead of it and explosive thunderstorms will develop where these two air masses meet.

More than 25 million people are under a level 3 of 5 risk of severe thunderstorms Sunday, according to the Storm Prediction Center. Nashville, Indianapolis and St. Louis are just a few of the major cities included in this wide-reaching risk. An additional 45 million people are under a level 2 of 5 risk in surrounding areas, including Dallas, Chicago and Cleveland.

Storms will begin late Sunday afternoon from Illinois to eastern Texas and get more violent as they expand east Sunday evening and overnight through much of the Mississippi, Ohio and Tennessee valleys.

Very large hail bigger than golf balls, damaging wind gusts and tornadoes are expected, according to the SPC.

The atmosphere will be primed for tornadoes and a few could be strong – rated EF2 or greater – and long-lived, the SPC warned.

Most of the strongest thunderstorms will occur after dark and increase the danger: Nighttime tornadoes are nearly twice as likely to be deadly as those occurring during the day, a 2022 study found.

Some storms will also dump heavy rainfall which could cause flash flooding anywhere from the South through the Midwest.

It’s already been a busy year for tornadoes even though the peak of severe weather season is still a few weeks away. There have been about 300 tornado reports since 2025 began, compared to 164 by the end of March 2024.

Only three years since 2010 have had more tornadoes in the first three months of the year: 2023, 2017 and 2013.

Last year saw a huge uptick in tornadoes later in the spring and activity continued through December, with nearly 2,000 tornado reports in total. It marked the second-most tornado reports on record, only behind 2017.

100 million people at risk of severe thunderstorms Monday

Powerful thunderstorms will continue as the sun rises Monday. Damaging storms from Sunday night could stretch from the Appalachians to Louisiana and Mississippi Monday morning.

Some of these thunderstorms could lose some steam during the first few hours of daylight before becoming severe again by the afternoon as they track east.

Thunderstorms could stretch over almost the entire East Coast by Monday evening. More than 100 million people from the South to the Northeast are under a level 2 of 5 risk of severe storms, according to the SPC.

Major cities from New Orleans to Boston all fall under the same risk level, but different regions could face slightly different threats.

Right now, the Northeast faces a greater risk of powerful wind gusts rather than tornadoes and hail. Atmospheric conditions to the south – from the mid-Atlantic to the Gulf coast – are more likely to support thunderstorms with all hazards, including hail and tornadoes.

Thunderstorms will continue overnight, mainly from the mid-Atlantic to the Northeast, before exiting out over the Atlantic Ocean Tuesday morning.

But it won’t be long before another severe thunderstorm threat arrives. The SPC has highlighted another very large area – from Texas through the Midwest – to watch for severe thunderstorms on Wednesday.

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