“So many of you have never seen an event like this,” Louisiana’s state climatologist warned, with New Orleans facing possibly the most snow it has ever seen.

Closures of schools, airports and businesses were taking effect in areas from southern Texas to Florida and South Carolina. Snow and ice could bring major travel disruptions and power outages.

Heavy snow is expected on Sunday in the Northeast before the coldest air in several years descends across much of the country starting on Monday, forecasters warned.

Hazardous snow, sleet and freezing rain disrupted travel plans and caused power outages in the Mid-Atlantic region, as bitter cold set in.

The Arctic air arrives this weekend and could linger into mid-January.