Snoqualmie Pass

We'll kick off the new year with a transition day as an incoming storm system heads north toward Snoqualmie Pass. If your resolution is to spend more time in the mountains, you can do it on Thursday with generally safe avalanche conditions. Travel hazards persist due to a lackluster start to our winter.

Happy New Year! Temperature inversions and east flow, resulting in upper-elevation sunshine and low-level clouds, have been the story for the last several days at Snoqualmie Pass. Numerous reports of warm temps, rollerballs on sun-exposed slopes, and cold, drier snow on shaded slopes have poured into our observation platform this week as backcountry travelers made their way into upper elevations around the Pass. But like many of us like to do, Mother Nature is going to kick off the new year with some changes. An incoming weather system will move toward Snoqualmie Pass on Thursday, increasing cloud cover ahead of a stormy period on Thursday night and Friday. A few showers could even begin during the day, but shouldn't be significant enough to create avalanche hazard.

That said, there are a few things to keep an eye out for. 

1. If rain falls on dry snow, you could see some small wet slides. This is more likely on shaded aspects or at lower elevations, where this week's sun hasn't already destabilized the surface snow.
2. If you’re pushing into higher, rocky, complex terrain, there could be a few isolated wind slabs still lingering in rocky chutes or near ridgelines. 

The real uncertainty surrounds what kind of precipitation will fall once the storm arrives. Snow, rain, or even freezing rain are all in the cards, given the inversions in place. It will likely be a messy transition until this new weather pattern settles into the zone. 

No matter what falls out of the sky, the snowpack should be well-suited to handle most of it. Our snowpack is considered strong and well settled. A new surface crust will likely develop on slopes where the sun has moistened the snow over the past few days. Be cautious - it could be slick once it forms, creating a good sliding surface for the incoming snow or a trip and a long fall for a weary traveler. Below the surface, you'll likely find the 12/24 crust down about a foot. While other crusts exist further down, we don't have many concerns at this time. 

As we turn the page on a somewhat disappointing December, remember that snow depths are still thin for this time of year. Open creeks, random holes, rocks, and bushes continue to make travel challenging.

New year, new you. Maybe it's time to submit an observation.