Thanksgiving travelers making their way home today — especially from the south — should arrive before dark to avoid snowy roads, the National Weather Service says.

The Medford office issued a winter weather advisory this morning for elevations 3,000 feet and above starting tonight through 10 a.m. Sunday. Forecasters expect accumulations of 1 to 4 inches on the Siskiyou Pass and high portions of Highway 140, particularly after 4 p.m.

It was already snowing in the Mount Shasta area this morning as a system from the west moves through, meteorologist Charles Smith of the Medford office said. Those in the valley can expect light rains this evening, while about an inch is expected along the coast, he said.