A rare and deadly winter storm descended across the southern U.S. on Tuesday, leaving inches of record-setting snow totals and halting travel for millions of Americans in Louisiana, Texas and Florida.

"I was born and raised in New Orleans," Ian Spooner told CBS News 24/7. "I can count on one hand how many times it snowed, and it never snowed like this." The last time New Orleans saw snow was in December 2004, according to the National Weather Service, and it was just half an inch.

Two people have been confirmed dead in Austin, Texas, city officials said.

With much of the southeast under winter weather advisories, including blizzard warning, here's how the cold and windy conditions are impacting the region:

At least 400 flights have been delayed and 350 more were canceled before midday Tuesday, according to the flight tracking company FlightAware. Airports in Houston and New Orleans were shut down as snow piled at the entrances. 

A spokesperson for the New Orleans Aviation Board said automatic doors were shuttered so they don't open and close during the hazardous weather event.

In Florida, the Tallahassee International Airport canceled all flights after 3 p.m. and suspended operations until at least noon on Wednesday. The state's governor and the governors of Georgia and Louisiana have all declared a state of emergency for the hardest-hit areas.

According to CBS News meteorologist Jessica Burch, 4 to 8 inches of snow have fallen across southern Alabama, Mississippi and Florida's Panhandle.

Some areas in the Panhandle recorded over half a foot of snow shattering long-standing snow records, CBS Miami reported. 

"This storm is unprecedented for its breadth and scope; we just don't have anything we can compare it to," NEXT Chief Meteorologist Ivan Cabrera said. "This will go down in history as the Gulf Blizzard of 2025."

The state of Louisiana saw a record-breaking snow total of over 10 inches in the city of Rayne. New Orleans saw nearly 9 inches of flurries. There are different snow reporting sites within New Orleans, but the oldest records from a sub-station that's no longer in service reported 10 inches of snow in 1895, and 14.4 inches in 1909.

Another reporting site at the New Orleans International Airport, which began recording snow accumulation in 1948, reported their highest total snow record as 2.7 inches in 1963. All that is to say, no one alive in the area has ever seen this much snow.

Videos posted by residents to social media showed not only the amount of snow but the speed at which the snow came down. The rough and unprecedented conditions led the National Weather Service to issue its first-ever blizzard warning for southern Louisiana on Tuesday.

A Blizzard Warning goes into effect when an area is expected to see frequent wind gusts over 35 mph, as well as reduced visibility from snow.

Winter weather advisories and winter storm warnings are also still in effect for parts of Texas, Alabama, Georgia, Florida and the Carolinas.

CBS News meteorologist Nikki Nolan contributed reporting.