(CNN) Much of the Southeast was seeing rain or snow as cold temperatures set in Thursday.

A winter storm that stretches from the Smoky Mountains in Tennessee to parts of Georgia and North Carolina has left more than 12 million people under winter weather advisories, watches or warnings.

Snow was expected to cover Georgia and Tennessee mountain tops, with some areas in higher elevations forecast to receive up to 6 inches, CNN meteorologist Michael Guy said.

"Portions of North Carolina are forecast to get more snow today than Washington or Philadelphia have received all season," CNN meteorologist Monica Garrett said.

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