(ABC News) -- As the Gulf Coast struggles to recover from an outbreak of tornadoes, millions across the nation are waking up this 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 airport, flights have been delayed as crews worked to de-ice planes.
Oklahoma got about 7 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 on Fayetteville, Ark., limiting roadway visibility.
All of that snowy weather in the South left a white trail everywhere it went, and today it's expected to bring at least six to eight inches to the lower Midwest. Today'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 and delayed inbound flights at San Francisco International airport, and caused a landslide in Oakland, almost crushing one driver to death.
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