A band of what forecasters are calling “heavy snow and disruptive ice” is expected to accumulate across the south through the end of the week. From the southern plains of Texas and Oklahoma to the coastal plains of Carolina, much of this winter precipitation is expected to fall in places where people are less accustomed to winter weather, and it is likely to cause dangerous driving conditions, power outages and school closures .

Important things you should know

• In the southern United States, it doesn’t take large amounts of snow or ice to disrupt everyday life.

• More than half a foot of heavy snowfall is expected to create hazardous traffic conditions along and south of Interstate 40 in Oklahoma, Arkansas and Tennessee.

• Further south, along and north of Interstate 20 from Texas to Georgia, the snow will likely turn to sleet and freezing rain as warmer air moves in above freezing temperatures at the surface.

• The region will continue to experience cooler temperatures next week, increasing the likelihood of hazardous travel conditions.

By early Thursday morning, snow was already falling across northern Texas and into Oklahoma as the storm took shape in the Gulf of Mexico before expected to move northeast. The heavier snow will likely remain in northern Texas and Oklahoma. The most likely snow total in Texas will be between 2 and 4 inches, mostly along and north of I-20, in an area that averages less than 2 inches per season.

Pending the potential impact, Dallas schools will remain closed Thursday and Friday. Gov. Greg Abbott used a news conference Wednesday to warn motorists: “Be careful. Be careful.”

“We’re not used to driving on ice and snow,” he told his fellow Texans. “We are not used to driving in such conditions.”

As the storm crosses the Gulf of Mexico Thursday through Friday, any slight change in its direction could result in rainfall that differs from what is forecast for a specific area. A slightly more northerly track would shift the heavier snow further north and raise the line of freezing rain and sleet. A more southerly track would have the opposite effect as the heavier snow would travel deeper south and northern areas would remain dry.

Wintry precipitation is expected in Texas, Oklahoma and Arkansas Thursday night through Friday. By early Friday morning it will continue to spread eastward across Tennessee, northern Mississippi, Alabama and Georgia. While winter storms are common in Tennessee, some areas like Memphis could see their highest two-day snowfall in 40 years.

Meteorologists in Nashville reminded locals not to get hung up on exact amounts because any snow could lead to dangerous travel in the region. In Atlanta, it’s been nearly 11 years since a mini-blizzard known locally as Snowmageddon paralyzed the city and became the punchline of a “Saturday Night Live” sketch.

Even though snow has fallen in the city since then, people may still be surprised to see the type of precipitation change throughout the day. What is initially expected to be snowfall Friday morning will likely turn to sleet and then freezing rain in the Atlanta metro area, turning untreated roads into ice skating rinks by the evening hours.

Across North Carolina, a similar scenario will emerge around midday Friday and continue overnight into Saturday. Accumulations of up to five centimeters are currently expected in the Mid-Atlantic region east of the Allegheny Mountains.

The storm is then expected to move away from the coast, where it will strengthen but remain far enough away to not pose a major threat to the Northeast.

The unusually cold weather on the East Coast is expected to last into next week, meaning there may be some more snow. And where snow has melted during the day, it can freeze again at night, creating ongoing transportation hazards.