By Robert Mittendorf

The Bellingham Herald

If you’re driving for the Thanksgiving holiday, weather and transportation officials are offering some early advice.

State Department of Transportation officials said state highways will see typical heavy holiday weekend traffic, and long delays are expected on Interstate 90 and on the ferries.

Google’s “Mapping Thanksgiving” page offered the following travel trips for the holiday:

■ Don’t leave Wednesday night.

■ Return on Saturday morning.

The heaviest holiday traffic in the Seattle area is from early afternoon to midnight Wednesday, according to Google — which analyzed the speed and location of Android phones with location services enabled.

The best times to be on the road in Seattle are 4 a.m. Thanksgiving Day and 3 a.m. Black Friday, Google said.

The worst times to be on the road in Seattle are 4 p.m. Wednesday and 4 p.m. Saturday, Google said.

Weather forecast

Foul weather could add to holiday traffic woes in Western Washington.

Meteorologists at the National Weather Service in Seattle are urging drivers to be ready for snow in the mountain passes and rain in the lowlands of Western Washington.

“Several rounds of snow are possible, with snow levels lowering below the passes,” the weather service tweeted Thursday. “Plan ahead now and make sure to keep an eye on the forecast.”

There’s an outside chance that snow will dust the foothills, forecasters tweeted.

At a minimum, travelers should pack a flashlight and batteries, cell phone charger and battery, ice scraper, tire chains, blanket, extra warm clothing, water and snacks, WSDOT said. It also helps to keep a full tank of gas.