Several inches of snow heading to Cascades this weekend

Several inches of snow heading to Cascades this weekend »Play Video
File photo of mountain snow
SEATTLE -- All this recent talk about endless stretches of sunshine, the driest two months in Seattle ever, an El Nino primed to wipe out the winter storms has probably left skiers and snowboarders seriously bummed.

But cheer up, we've got some good news for you. Just don't go smiling to anyone who has to drive over the passes anytime soon.

Our first real shot of cold air is on its way for this weekend and into early next week, poised to bring the first decent mountain snows of the season.

The inaugural Winter Storm Warning has been issued for the mountains this autumn and is in effect from 11 p.m. Friday through 5 p.m. Saturday for the Olympics and Cascades above 3,000 feet.

As much as 4-8 inches of snow is possible although Snoqualmie Pass would be on the lower end of that forecast. But up above 5,000 feet, even more snow is expected -- perhaps up to a foot or more.

On the other hand, Stevens Pass could also reach around a foot thanks to some help from the Puget Sound Convergence Zone.

The mountain snow is courtesy of a large area of low pressure that has been "chillin' out" (literally and figuratively) in the Gulf of Alaska but is now dropping south to where it will park just off our coast. That will not only bring in much colder air from the Last Frontier but also plenty of moisture in the form of scattered showers.

In addition, strong westerly upper level winds will enhance the shower activity in the mountains as that air slams into the western slopes and its moisture is essentially wrung out like squeezing a sponge.

Snow levels will have dropped to 4,500 feet by late Friday and then down to 3,000 feet by early Saturday morning. Showers may start as rain in Snoqualmie Pass but will likely changeover to snow by morning.

In the lowlands, it's still all rain (we're not that far into autumn just yet) but it'll be chilly. Temperatures over the weekend will spend much of the day in the 40s -- maybe eke 50 or 51 at the buzzer -- amid a mix of showers and sunbreaks. The atmosphere is moderately unstable to where we could see a rogue strike of lightning as well.

Cold air with its 3,000-foot snow levels are expected to remain in place through the middle of next week, although as upper level winds weaken a bit, the mountains won't see as much snow, but light snow showers will remain in the forecast.

Long range forecasts bring some moderating warmer air toward the end of the week., but in the meantime, if you see a skier smiling a bit, you'll know why.