A once-in-a-generation winter storm is sweeping through the South as much of US deals with frigid temperatures

CNN
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Roughly 40 million people from Texas to the Carolinas are under winter weather alerts as a rare winter storm amid bone-chilling temperatures brings potentially historic snowfall to cities unused to harsh, cold weather.

Here’s what’s happening now:

• Historic storm underway: Snow is falling over parts of southeast Texas, Louisiana and Mississippi early Tuesday morning and creating treacherous conditions. An area stretching from Houston into southern Louisiana has already recorded 1 to 2 inches of snow with more on the way. A record amount of snow is forecast for New Orleans and other cities along the Gulf Coast.

• Unprecedented blizzard warning issued: Heavy snow and strong wind gusts are combining to create whiteout conditions in southern Louisiana, where snow totals of 3 to 6 inches could be widespread. It prompted the first-ever blizzard warning anywhere along the Gulf Coast from the National Weather Service in Lake Charles, for parts of southern Louisiana and far eastern Texas.

• Widespread closures: Large sections of Interstate 10 — the Gulf Coast’s major thoroughfare — in Texas and Louisiana are closed Tuesday as snow and some icy mix make travel difficult to impossible. Schools and government offices are closed Tuesday throughout the Gulf Coast and states of emergency are active in Louisiana, Georgia, Alabama, Florida and Mississippi.

• Deadly cold: Low temperatures and wind chills from the Canadian border to the Mexican border are hitting dangerous levels for the second consecutive day. Wind chills Tuesday morning dropped into the teens for much of the Gulf Coast with single digit values in northern Texas. The cold has already been implicated in one death in Milwaukee.

Brutally cold temperatures are allowing an incredibly unusual storm to unfold along the Gulf Coast.

Snow, and an icy mix of snow, sleet and freezing rain, expanded in the early hours of Tuesday and will ramp up throughout the morning.

The sweeping system is “a generational winter storm event,” the National Weather Service said Monday — and urged those along its path to take it seriously.

Roads overnight and Tuesday will be “extremely hazardous if not impossible for much of the area, and travel is highly discouraged,” the service said. Hundreds of flights in the region already have been cancelled. And schools are closed in states including Texas, Louisiana and Georgia.

The complex mess of wintry weather will spread east to reach more of Mississippi and into Alabama, Georgia, the Carolinas and the western Florida Panhandle throughout the day. Tuesday’s snowfall could break records last set decades ago and possibly rival records from the late 1800s.

The rare winter storm comes as more than 220 million people in the US are affected by bitterly cold air. The Upper Midwest and Northern Plains recorded wind chills to 50 degrees below zero Monday and were experiencing 40 degrees below zero Tuesday morning — temperatures that can cause frostbite on exposed skin in a matter of minutes.

The eastern two-thirds of the US experienced dangerous cold Tuesday morning.

Air and road travel halted; schools shut down

Officials in affected states in the South cautioned people to stay off the roads, keep faucets dripping to prevent pipes from freezing, check batteries in smoke and carbon monoxide detectors and refrain from using cooking stoves to heat homes.

Governors in Louisiana, Georgia, Alabama, Florida and Mississippi have declared states of emergency, while Texas authorities have directed state agencies to mobilize resources for the rare snowfall.

“Most of us haven’t experienced this combination of bitter cold and significant snow ever in our lifetime,” Louisiana climatologist Jay Grymes said Monday.

Forecasters say travel could be paralyzed along the Interstate 10 corridor, which could receive snowfall totals of 3 to 6 inches, for days. Cold weather will lock any snow and ice that falls into place, keeping roads hazardous.

Disruptions were also reported in the skies.

There were more than 1,900 flight cancellations within, into or out of the US early Tuesday, with most of those flights coming from Texas and Louisiana, according to the flight tracking website FlightAware.

Vehicles pass a sign displaying Winter storm related operations Monday in Houston ahead of predicted several inches of snow and possibly ice in Southeast Texas.

Houston’s two major airports, George Bush Intercontinental and Hobby, are closed Tuesday, while Hartsfield-Jackson Atlanta International Airport, the world’s busiest, is pretreating roadways and airfield surfaces in preparation for the winter weather, according to spokesperson Andrew Gobeil.

NASA’s Johnson Space Center in Houston said it will be closed Tuesday and Wednesday due to the extreme weather. Port Houston said its facilities will be closed on Tuesday as well.

Schools across the Deep South were closed or moved online Tuesday from Texas to Florida. In Georgia, Gwinnett County Public Schools, the state’s largest school district, has moved all its classes online. The Houston Independent School District, the largest in the Lonestar state and the eighth largest in the country, will also be closed until Wednesday.