Tornadoes Are Expected in Parts of the South on Friday

Severe thunderstorms were expected to sweep across parts of the Mississippi and Ohio Valleys on Friday, raising the risk of tornadoes, damaging winds and hail for millions of people, forecasters said.

The storms were expected to ramp up across the region beginning in the afternoon and last through the evening hours, according to the National Weather Service’s Storm Prediction Center.

More than 2.3 million people from southwest Tennessee through portions of Arkansas, Mississippi and northeast Louisiana were under a moderate risk for severe weather. A larger area in those states was under an enhanced risk.

“For the moderate area, tornadoes are likely and some could be strong,” Dan Byrd, a meteorologist with the Weather Service in Jackson, Miss., said Friday morning. Damaging winds up to 80 miles per hour and large hail were also possible in the area under moderate risk.

“The time frame we’re looking at is from about 5 to 11 p.m., and then it’s going to shift into central Mississippi into the early overnight hours,” he said. “Then it’ll move out of the state, probably about 2 or 3 in the morning.”

“It really looks like those evening hours are going to be that key period, when we could see the strongest potential for tornadoes,” Mr. Byrd said.

A similar forecast was issued for Little Rock, Ark., where meteorologists said that hail up to the size of a quarter was expected and that “all modes of severe weather” would be possible on Friday, including tornadoes.

Because of heavy rainfall associated with the storms, areas from the Ozarks to the Ohio Valley were under a moderate risk for excessive rainfall. More broadly, about 18 million people from eastern Oklahoma east to Ohio and West Virginia were under a flood watch.

Officials in Mississippi on Thursday urged residents to find a safe place in the event of tornadoes, while officials in Tennessee reminded residents that spring weather could be unpredictable.

Severe weather season in the South reaches its peak during the spring months of March, April and May, meteorologists said. Thunderstorms are classified as severe when they produce hail of at least the size of a quarter or wind gusts of at least 58 m.p.h.

Earlier this month, powerful storms swept across the South, leaving at least 12 people dead and hundreds of thousands of customers without electricity. Heavy rains, severe winds and tornadoes damaged homes in at least eight states.

And at the end of February, tornadoes injured at least a dozen people in Oklahoma.