The National Weather Service on Monday predicted a significant snow and ice event affecting northwest Oregon and southwest Washington.
According to the Weather Service, it will create dangerous travel conditions and possible power interruptions as snow accumulates on the Willamette Valley floor Wednesday followed by sleet and freezing rain later Wednesday and Thursday. The ground is likely to remain frozen with cold weather late in the week and during the weekend.
The brunt of the storm will affect the northern part of the valley. In the central valley, precipitation is forecast for midday Wednesday with snow likely through the afternoon. Snow may then transition to ice and then rain Wednesday evening and Thursday. Several inches of snow are possible Wednesday afternoon.
In the southern valley, precipitation is likely to begin as snow or freezing rain briefly Wednesday morning, with a quick burst of minor accumulation of snow or ice, shifting to rain Wednesday afternoon through Thursday.
To the north, precipitation is expected mid to late afternoon, snowing through Wednesday and Thursday, with a potential switch to sleet and freezing rain Wednesday night. Significant accumulations of snow or ice is possible.
The Cascades could accumulate 6 to 12 inches of snow through Thursday.
Forecasters reported “moderate confidence” in their predictions for the central and southern Willamette Valley.
The forecast is for a cold, gusty easterly offshore flow setting up late Tuesday and Wednesday, while a low-pressure system approaches the coast from the southwest Wednesday, bringing a warm front onshore.
Associated precipitation will spread in from the south to the north, starting at the central Oregon coast and southern Willamette Valley by Wednesday morning.