(NEW YORK) -- As the Gulf Coast struggles to recover from an outbreak of tornadoes, millions across the nation are waking up Wednesday morning on the busiest travel day of the Christmas season to cope with more severe weather that promises to upset the travel plans of millions.
"Traveling will definitely be affected as people go home for the holidays," Bob Oravec, lead forecaster for the National Weather Service, told ABC News. "Anywhere from the Mississippi Valley into the Ohio Valley and the Northeast, there's definitely going to be travel issues as we have heavy snow and some very high winds."
That large storm has been pounding not just the Gulf Coast but most of the South from Oklahoma to Arkansas, and Texas, where Dallas had a rare white Christmas.
In Lubbock, Texas, more than an inch of snow fell, making it difficult for some drivers to stay on the road. At Dallas/Fort Worth International Airport, flights have been delayed as crews worked to de-ice planes.
Oklahoma got about seven inches of snow across the state, making for treacherous road conditions. A 21-car pile-up in Oklahoma City temporarily shut down a major roadway through the state. No one was seriously injured.
Arkansas also got a rare Christmas Day snow storm, with an estimated 10 inches falling in Fayetteville, limiting roadway visibility.
All of that snowy weather in the South left a white trail everywhere it went, and on Wednesday, it's expected to bring at least six to eight inches to the lower Midwest. Wednesday's severe weather could cause potential delays at airports in St. Louis, Louisville, Ky., Indianapolis and Cincinnati.
In Northern California, residents were socked with the third storm in three days. Wet weather spread from the Bay area through the Sierras, delaying inbound flights at San Francisco International Airport and causing a landslide in Oakland that almost crushed one driver to death.
The severe weather system in the South has been moving overnight, and a front with heavy rain and wind is forecast for the Northeastern corridor late Wednesday night and into Thursday morning.
"The [weather in] big cities from Washington up to Philadelphia and New York City will mostly be in the form of rain," Oravec said. "There may be a brief period of snow from the nation's capitol this morning up into Philadelphia and then to New York City. But the track of the storm currently suggests that the precipitation will definitely change over to rain."
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