Snow, tornadoes and freezing rain are coming to a wide swath of the country

By Mihir Zaveri, New York Times

A storm system that was sweeping across the country Monday left at least seven people dead over the weekend and placed more than 60 million people under winter weather advisories and warnings with threats of continuing snow, freezing rain and other types of severe weather.

The seven people all died in crashes on slick, icy roads Sunday in Nebraska and Missouri, authorities said. And multiple tornadoes touched down across Louisiana, destroying buildings, trees and telephone poles.

The storm system was expected to cause more chaos as it swept east from Monday evening into Tuesday, continuing to bring a variety of severe winter weather to Colorado and the Midwest and up through Boston, said Patrick Burke, a meteorologist at the National Weather Service’s Weather Prediction Center.

“It’s really wide ranging,” he said.

Many parts of the country were already seeing rain Monday morning. Burke said the effect of the weather would intensify and spread.

Here’s a look at how some of that is expected to play out and what it might mean.

Weekend Weather Leads to Seven Deaths, Plus Flight Cancellations

Some parts of Nebraska and the Midwest were already reeling from several inches of snow and icy roads this weekend. The National Weather Service in Indianapolis reported that some areas had seen more than 4 inches of snow as of Sunday night.

In eastern Nebraska, slick roads Sunday morning led to a four-vehicle crash that left three people dead, said Cody Thomas, a spokesman for the Nebraska State Patrol.

In eastern Missouri, a car slid off an icy roadway late Sunday afternoon and fatally struck three people who were standing outside another car that had lost control in the same area, according to the Missouri Highway Patrol. In a separate episode in Missouri earlier Sunday, a man died after he was thrown from his vehicle as it slid off the road and overturned, the highway patrol said.

At the Lambert-St. Louis International Airport, about 20 arriving flights and 20 departing flights had been canceled as of 6 a.m.

Tornadoes and Thunderstorms in the South

Storm systems sweeping in from Texas brought multiple tornadoes and tornado warnings across Louisiana on Monday, and they were expected to bring more strong weather farther east to Mississippi.

“It was a pretty significant tornado outbreak here,” said Kent Kuyper, a meteorologist with the National Weather Service in Lake Charles, Louisiana.

Early Monday afternoon, a tornado passed through the Alexandria, Louisiana, area with a particularly long track — possibly around 60 miles, Kuyper said. There were reports of extensive structural damage, he said.

There were also reports of tornado damage in northern Louisiana, between Cotton Valley and Minden, and in other areas throughout the state, said Davyon Hill, a meteorologist with the National Weather Service in Shreveport, Louisiana.

The National Weather Service in Jackson, Mississippi, said that “severe weather” had been likely Monday and that “severe storms capable of producing damaging wind gusts, a few tornadoes, and large hail are expected.”

Thunderstorms are also expected to intensify in states around the Gulf of Mexico.

“Fueled by increasing moisture, warmth and instability from the Gulf of Mexico, these thunderstorms will likely become strong to severe as they sweep across the central and eastern Gulf States later today into tonight,” the Weather Service said.

More Snow Across the Country, With Some Deep Pockets

A large stretch of the country, from Colorado to the Northeast, would probably see 1 to 2 inches of snow through Tuesday, Burke said.

But there would be some deeper pockets in the St. Louis area and parts of New York around Buffalo and in the Catskills, he said.

The Weather Service said it expected up to 7 inches of snow in some parts of the St. Louis area, making travel “extremely difficult, if not impossible.”

In and around the Buffalo area, the service said Monday morning that it expected 3 to 5 inches of snow starting Monday night.

Freezing Rain in and Around Pennsylvania

Burke said freezing rain and a “glaze of ice” would hit southern Pennsylvania, western Maryland and the mountains of West Virginia.

The National Weather Service in State College, Pennsylvania, estimated up to half an inch of ice accumulation in Somerset County after “snow, sleet and freezing rain” move into the state overnight.