Willamette Valley Wintery Forecast

Expect a switch to all snow by mid-morning on Sunday

Some snow is expected to fall this weekend, all over Oregon. Photo: Bonnie King Salem-News.com

(PORTLAND, Ore.) - Very cold air will move into the region late Saturday night through next week. Rain will begin at low elevations Saturday afternoon, before changing over to snow early Sunday morning. Above 2,000 feet, this moisture will fall as all snow.

SNOW AMOUNTS AND TIMING:

I-5 Corridor from Kelso/Longview through Portland metro area: Rain, possibly mixed with a little snow, begins late Saturday afternoon, before changing to all snow early Sunday morning, sometime between about 2 am and 7 am as snow levels lower to the valley floor. Expected snowfall amounts are generally 1 inch or less, with local accumulations up to 2 inches possible in the higher hills.

Through the rest of the Willamette Valley (McMinnville/Aurora through Eugene): Rain begins Saturday evening and continues through early Sunday, when some snow may begin to mix in with the rain. Expect a switch to all snow by mid-morning on Sunday with occasional snow continuing through the evening. Total snow accumulations expected to be generally 1 inch or less, with highest amounts from about Marion County north.

Coast Range: Snow levels Saturday afternoon begin between 1,500 and 2,000 feet, but lower to the surface by Saturday night. Expect 1 to 2 inches of snow, with the highest amounts in the higher elevations and northern Coast Range (generally along and north of Highway 22).

Coast: Primarily rain through early Sunday, then transitioning to snow around sunrise Sunday. Snowfall accumulations between 0 and 0.5 inches.

OUTLOOK FOR NEXT WEEK:

Cold air will remain in place through much of next week, but it is expected to remain dry from Monday through at least Wednesday across the region.

Low temperatures in the valley Monday night through at least Wednesday night are expected to be 10° to 20° with afternoon high temperatures not getting above freezing.

At the coast, low temperatures are expected to be 20° to 30° with high temperatures in the 30s, generally above freezing.

FORECAST CONFIDENCE:

High confidence in accumulating snow for Cascades, Cascade foothills, and Coast Range starting late Saturday afternoon, and moderate confidence in snowfall amounts.

• Moderate confidence in accumulating snow and snowfall amounts in the lower elevations.
• Low to moderate confidence in accumulating snowfall at the coast.
• High confidence in a very cold, but dry weather pattern for Monday through at least Wednesday.

Source: Marion County Emergency Management