An amplified weather ridge of high pressure off the coast will result in a northwest flow over the area into Tuesday. However, a weak wave of low pressure will quickly slide through the state today bringing with it a 30% chance of rain mixed with snow showers and afternoon high temperatures in the lower to mid-40’s. For Tuesday, afternoon a large area of low rapidly intensifies as it nears the Southern Oregon coast. This will set the stage for increasing winds, a good chance for accumulating snow and much colder temperatures.
Increasing clouds in our Tuesday forecast with winds out of the northeast 10-20 mph with gusts to 25 mph, a 50% chance of snow late afternoon/early evening with highs in the upper 30’s.
Tuesday night through Thursday, that large, deep low pressure system will track through Oregon bringing gusty northerly winds, some areas of snow and will draw-in much cooler, Canadian air into the Inland Northwest. Confidence levels are high for the general shift in the weather pattern and impacts.
Our main uncertainty with the forecast revolves around the exact wind speeds that materialize Wednesday and Wednesday night. Cloudy skies for Wednesday with a 40% chance of snow, northeast wind 15-25 mph gusting to 30 mph with afternoon highs in the lower 30’s. With the strong wind, expect cold wind chills.
On Thanksgiving Thursday, the Wenatchee Valley and the rest of Northcentral Washington will see mostly cloudy skies with afternoon high temperatures unseasonably cold with highs near 30 degrees. Expect overnight lows only in the mid-teens.
Then for Friday and the upcoming weekend it be cold but largely dry as a stable weather pattern develops. The area of low pressure over Oregon will continue to fill and slowly drift into the Central U.S. while another low drifts into the Eastern Pacific. High pressure will strengthen between these features and deliver the dry weather. We will see sunny skies each day Friday through Sunday with afternoon high temperatures near 30 degrees with overnight lows in the lower to mid-teens.