Winter weather alerts span across Oregon, Washington Thursday

PORTLAND, Ore. (KOIN) -- Ice, snow, and extreme cold alerts stretch across western Oregon and parts of southwest Washington in preparation for a major winter storm this week.

Strong and cold easterly winds are helping ramp up the winter weather potential across the Pacific Northwest as moisture slides into place from the Pacific Ocean. Everything from dangerous wind chill factors, to snow, to sleet and ice is possible Thursday through Friday. A KOIN 6 Weather alert is in place through the end of the week and the National Weather Service also warns local communities.

Portland's Winter Storm Warning

The Portland National Weather Service has issued a Winter Storm Warning for the greater Portland, Vancouver metro area. This goes into place Thursday morning and lasts through 10 a.m. Friday. That's where Portland could see ice from a glaze to nearly a tenth of an inch. Snow could also be part of the mix. That's where accumulation will be near anywhere from 1-4" depending on locations. Some visible snow accumulation may be lost due to wind blowing the snow elsewhere.

Coastal and Cascade's Winter Weather Advisory

The coast won't miss out on the winter weather potential this week. Ice is likely over the higher elevated locations of the Coast Range. Some coastal communities could see a mix of snow and ice. Ice accumulation could be near a tenth to a quarter of an inch. The higher elevations of the Cascades will likely see closer to 6-12" of snow through Friday evening.

Central, southern Willamette Valley's Ice Storm Warning

More accumulative icing is expected south of Wilsonville. A warmer pocket of air above the valley floor could help melt snow and turn it into rain. It's the rain falling rain on a subfreezing surface that increases the ice potential for areas around Salem. Nearly an inch of snow is possible along the central and southern Willamette Valley. Hiding beneath the snow could be a layer of ice that nears three-tenths of an inch.

Extreme Cold Warning for the Gorge

Extreme cold will increase the threat of hypothermia as wind chill or "feel-like" temperatures fall to nearly zero degrees. Gusty winds will continue to keep temperatures dangerously cold through the mid-morning hours Thursday. This cold air will remain in the northern Willamette Valley through the early morning hours of Saturday.