Transportation officials are urging Thanksgiving travelers to exercise caution because of a record number of travelers and wet, slick roads.

AAA estimates about 592,000 Oregonians will be traveling for Thanksgiving. In the Pacific region, which includes Oregon, Washington, California, Alaska and Hawaii, almost 8 million people will be traveling, a 2 percent jump from 2015. About 86 percent of people will travel by car, the automobile club said.

Lower gas prices — the second-lowest prices during the Thanksgiving holiday since 2008 — and decreases in rental-car rates are among the reasons for so many travelers.

Travelers should expect wet, slick roads throughout the region. Southwest Oregon received a mix of rain and snow overnight, with more in the forecast.

Trace amounts of snow fell as low as 1,500 feet in Jackson County, while 1 to 3 inches fell at the 4,000- to 4,500-foot level. Areas at 5,000 to 5,500 feet saw up to 10 inches.

The Oregon Department of Transportation's Trip Check website lists several reports of wet and slushy roads in the region, but a presentation from the National Weather Service says Wednesday might provide a good window for travelers because of some clearing.

"It's not to say that there won't be any snow in the passes, but it will be more off and on, and the majority of travelers Wednesday should encounter favorable weather," meteorologist Brad Schaaf said.

The next system is expected to arrive Thursday evening, with more rain and snow expected to fall on the passes. Up to four inches could fall on the Siskiyou Summit between Thursday night and Saturday morning, with multiple feet expected at Crater Lake and Diamond Lake over the same period. About 20 inches could fall on Mount Ashland, weather officials said.

ODOT said holiday travelers should be prepared. Travel on a full tank of gas, and pack water, snacks and blankets. Motorists should also be well-versed in how to use their tire chains.

— Reach reporter Ryan Pfeil at 541-776-4468 or rpfeil@mailtribune.com. Follow him at www.twitter.com/ryanpfeil.