Avalanche Forecast

A system passing through in Northwest flow Saturday night and Sunday morning should transition to generally light snow showers by mid-day Sunday. A warm front approaching from the west should hold off on producing another round of moderate snow until late Sunday afternoon.

Generally shallow, new storm slab formed Saturday night and Sunday may be sensitive during slight warming Sunday as denser snow layers on top of lower density snow from Saturday night. 

Overall the snow received over the last 2 weeks continues to settle and stabilize. Human triggered large or very large avalanches are becoming unlikely but are still high consequence if able to step down to poorly bonded previous storm or wind layers. Cornices have grown large and are still reported to be sensitive. A cornice failure could provide a large enough natural trigger to trigger a large and destructive avalanche. 

There's plenty of new snow to go around...continue your careful snow pack evaluation and cautious terrain selections on Sunday.

Recent Northwest Weather

An extended mild and dry period occurred the latter half of January generally causing a crust to form in all areas. Very cold weather followed in early February which generally produced low density snowfall and faceting near and just above the crust.

Friday afternoon through Saturday morning was the first relative break in a seemingly endless storm cycle over the last two weeks. Constant frontal systems produced periods of strong winds and heavy snowfall. The water equivalent over the past 12 days is about 7 inches with snowfall about 5.5 feet at the NWAC weather station at Hurricane Ridge.

Observations for Washington Cascades near and west of the crest

Several avalanche cycles have been seen in the last 2 weeks. The forecast attention near and west of the crest including the Olympics will be focused on recent storm and wind layers.  The last natural cycle likely occurred during the middle of the week when the road was closed. NPS employees found avalanche debris up to 8' deep just off the Hurricane Ridge road at 3600 feet while plowing the road Thursday. The start zone was likely in the near-treeline zone on a S-SE aspect. 

The late January crust layer and associated weak layers are now deeply buried by all the new storm snow, but still producing areas of collapsing and large whumpfing as reported in a NE meadow below treeline by a frequent TAY-er in the Hurricane Ridge area. The same skier had pictures of some very large cornice collapses.

On Friday NWAC observer Katy Reid Friday found stubborn but still possible to ski trigger wind slab on northerly aspects above treeline. She also observed quickly releasing wet loose avalanches on below treeline on solar aspects reacting to the strengthening February sunshine. Finally, new surface hoar around 4mm thick formed on all wind and sun sheltered aspects near and below treeline and may have been buried by the light new snow with little wind Saturday. 

Road side roller balls and small wet loose on solar slopes at Hurricane on Friday by Katy Reid.

The mid and base pack at Hurricane should still consist of mostly stable crusts and melt form layers from periods of warm weather earlier this winter.

Keep an eye on your riding partner until the deep new snow further settles and the risk of SIS subsides.