A second round of snow is expected to fall on Oregon's mountain passes Saturday night into Sunday morning.

The system is expected to bring the coldest temperatures of the season and drop snow levels as low as 2,000 feet.

The weather began impacting drivers crossing the Santiam and Willamette passes, and in the Mount Hood area, Thursday night.

“We’ve had some significant snow this season, but this seems to be the first one that could stick — that won’t be followed by a warm-up,” National Weather Service meteorologist Matthew Cullen said. “People driving over the mountains will want to be prepared.”

The system could bring up to a foot of snow at pass level, according to KGW forecaster Brian Brennan.

The Columbia River Gorge may even see a mixture of rain and snow.

"East winds through the Gorge may make things chilly enough for overnight for rain/snow mix and light accumulations around 1,000 feet," Brennan said. "Same goes for the Hood River Valley."

The Willamette Valley isn’t expected to get any snowfall, but temperatures will dip to as cool as 38 degrees on Sunday night.

“This looks like it could be that transition period when we move from the warmer, rainier systems into the cooler, more winter-like systems,” Cullen said.

Zach Urness of the Salem Statesman-Journal contributed to this report