Avalanche Forecast

We are just coming out from under an avalanche warning in the West-North zone. The Mt Baker area has received 6.52 inches of water since Wednesday afternoon. That is a lot of water in 48hrs! At higher elevations most of this fell as snow. Several large, natural, and triggered avalanches were reported Thursday.  A break in the weather Saturday should allow the avalanche danger to slowly decrease.

At lower elevations a wet snowpack exists. In some locations glide cracks have been reported. Even though the temperatures have cooled, it will take several days for the snowpack to freeze. Stay out from under any slope where you see large crevasse-like cracks in the snow.

January 4, 2019

The first few days of 2019 were active here in the Northwest. A strong weather system impacted the region bringing warm temperatures, heavy precipitation, and strong winds. This weather system did not impact the forecast areas equally. Even within the same forecast zone we can see wide discrepancies in precipitation numbers. The snowpack you encounter this weekend will be largely dependent on where you go and the elevation at which you travel

Storm Precipitation Totals as of Friday Afternoon

Hurricane Ridge: 2.41”

Mt Baker: 6.52”

Stevens Pass: 2.58”

Snoqualmie Pass: 2.27”

Crystal Mountain: 0.52”

Paradise: 2.23”

White Pass: 0.55”

Washington Pass: 1.05”

Mission Ridge: 0.31”

Mt Hood Meadows: 0.51”

A few big stories stand out in the current snowpack: recent avalanche warnings in the northern zones, persistent slabs in the western areas, and a complex and weak snowpack in the eastern zones.

The northern zone experienced the brunt of this latest weather system. This led to two days of avalanche warnings and at least one large natural avalanche cycle. It's tough to say what the snowpack looks like in areas near and above treeline, but we know those areas received substantial new snow.

Photo: Large natural avalanche at Mt Baker Ski Area during the recent storm. -Mt Baker Ski Patrol

Earlier in the week we began forecasting a new persistent slab in our west-slope zones. A layer of buried surface hoar produced avalanches last Saturday, Sunday, and Monday. How did that layer fair after this recent round of weather? In locations like Mt Baker and Paradise, it was well tested with heavy precipitation. In other locations, less water may not have adequately stressed the weak layer. As visibility improves and more observation come-in the picture may become more clear.

Photo: Large remotely triggered persistent slab avalanche in the Crystal backcountry: Jeremy Allyn

In the eastern zones a complicated and weak snowpack exists. Several persistent weaklayers have plagued these regions most of the winter. Don’t expect this to change anytime soon. Snow profiles and snowpack test can give you a glimpse into the persistent layer. Remember, snow profiles cannot prove the absence of a weak layer or that a layer has “healed.”

Photo: Large remotely triggered slide on buried surface hoar from Christmas above Leavenworth on 12/31: Matt Primomo