A dangerous winter storm spread more than 1,500 miles across the southern US on Tuesday with historic snowfall, prompting the first-ever blizzard warning for the Gulf Coast. 

A historic January storm dumped so much snow on the U.S. Gulf Coast on Wednesday that it brought Houston and New Orleans to a near standstill over the past two days, and left parts of the Florida Panhandle blanketed with snow as cold as Chicago.

Some locations in northern Florida, southern Georgia and southeastern South Carolina received up to 4 inches (10 cm) of snow, sleet and freezing rain as the storm passed through the area on Wednesday, the National Weather Service said.

Florida has already broken its all-time snowfall record, with 9 inches of snow falling in Milton, a western Panhandle town near Pensacola, according to Frank Pereira, a meteorologist at the National Weather Service's Weather Prediction Center.

Before the storm, Milton Mayor Heather Lindsay said she hadn’t seen a single snowflake fall in the city since 2014.

“We’re taking it in stride, but everything is shut down,” Lindsay said, adding that the city has no snow removal machines and most residents don’t even own a snow shovel.

But kids are using kayaks and inner tubes as sleds and enjoying the snowy day, he said.

Colder winds began to blow as precipitation eased on Wednesday and will continue through at least this weekend along the Gulf Coast and East Coast.

The cold is still there, meteorologist Frank Pereira said. In Tallahassee, the capital of Florida, where temperatures typically hover around 60 degrees in January, a low of 4 degrees Fahrenheit (-15 degrees Celsius) is expected on Wednesday.

The winter storm had already devastated major Gulf Coast cities such as Houston, which received 4 inches (10 cm) of snow, the most the city has seen since 1960. In the New Orleans area, some places received a record 10 inches (25 cm) of snowfall, turning Bourbon Street white on Tuesday.

Snowfall a rare occurrence in Louisiana

Justin Daffron, chief development officer for Covenant House in New Orleans, said his shelter is operating at full capacity and managing to meet the demand, even though Louisiana is under a snow emergency.

“I think it's different because hurricanes are common in New Orleans, and we're not accustomed to harsh winter weather,” he said.

This took everyone by surprise because for those of us who have seen winter weather here before, it was basically a dust storm.

At least 12 people have died as a result of the storm, according to the Texas Department of Public Safety, including five in Zavala County, Texas, who died in a single-car crash on Highway 57 on Tuesday. Two other deaths were reported in Texas due to the cold snap, including one in Austin, officials said.

Officials announced other cold-related deaths in Alabama and Georgia.

Meteorological department issued warning

About 20 million people across the region were under winter weather advisories and warnings on Wednesday, with the National Weather Service warning people about frostbite and hypothermia and road travel hazards.

These travel impacts could last for several days, the service said, due to historically heavy snow accumulation, cold temperatures and a lack of equipment to clear roads compared to northern regions.

According to Poweroutage.us, more than 90,000 homes and businesses were without power from Texas to Georgia and Florida. Many schools and local government offices were closed, while many highways across the region were slippery and covered in snow and ice.

The storm forced several airports, including Houston's George Bush Intercontinental Airport and Dallas-Fort Worth International Airport, to be temporarily closed overnight and early Wednesday morning. More than 1,400 flights were canceled in the U.S., many of them in the Southeast, and 1,200 were delayed, according to tracking site FlightAware.com.

US liquefied natural gas company Freeport LNG said on Wednesday it shut its export plant in Texas on January 21 due to power problems during a winter storm, and will keep it closed until power supplies are stabilized.

The US Northeast suffered another day of bitter cold. The lowest temperature recorded in the United States on Wednesday was -27 degrees Fahrenheit (-32 C) in Davis, West Virginia, according to the National Weather Service.