Cold air could combine with warmer rain to coat the streets with ice.
For about a week the Willamette Valley, Portland and Vancouver have dealt with freezing fog. A storm system approaching Wednesday will bring rain, but it could start as freezing rain.
It'll depend on how cold temperatures get overnight. The lows are expected to be near freezing.
Rain is expected to start Wednesday morning.
The National Weather Service has issued a Freezing Rain Advisory.
It's possible that the freezing rain will be spotty with some areas just getting rain.