Mountain Weather Forecast

Weather Synopsis

It's hard to believe the difference between the northern and southern ends of our forecast region this afternoon. Very stormy weather continues to hammer the western Olympics and North Cascades, meanwhile sunny, all be it, breezy conditions describe areas the Mt Hood and southern zones. A trough continues to dig south off the coast, focussing a narrow atmospheric river (AR) right at Vancouver Island. Satruday night, the trough will continue to elongate causing the main precipitation band to lift further north. This should draw most of the rain and snow near and north of the Canadian border. Even as showers recede, winds will not. Gusty conditions should continue throughout the night with the strongest wind speeds near Hurricane Ridge, Mt Baker, Mt Saint Helens, and Mt Hood. 

For most areas, Sunday should start relatively dry. Areas further north should be cloudier than locations further south. The trough responsible for the AR splits in half, cutting off the main moisture tap to our system. What's left of the storm then drifts inland during the day. As a result, the Olympics and North Cascades will once again see the bulk of the precipitation. Expect stormy weather, periods of heavy rain/snow, and strong and gusty winds. While there's still some uncertainty about the timing of the precipitation, it looks like most areas from near Hwy 2 southward stay dry until late in the afternoon. Precipitation eventually reaches the East South and Mt Hood zones Sunday evening. 

The storm continues to push inland Sunday night with moderate rain and snow, strong winds, and cooling temperatures across most of the forecast region. By early Monday morning, the system has exited to the east. Low level moisture and onshore flow should keep the west slopes and passes cloudy with a few spotty showers. Meanwhile. the eastern zones dry out, with generally filtered sunshine and maybe even a few sun breaks. By late in the day, the entire region starts to enjoy a brief break between storms.