Avalanche Forecast

Thursday should remain cool with sunbreaks and scattered snow showers, mainly in the afternoon. Very light new snow amounts are expected, if any. 

Lingering wind slabs should continue to heal and become less sensitive to human triggering Thursday. Wind slabs should be isolated and confined to specific steep terrain features, more likely on N-E-S aspects near and especially above treeline. 

Storm slabs will not be listed as an avalanche problem Thursday as they continue to strengthen and bond. 

Loose wet avalanches will not be indicated as an avalanche problem, but watch for wet surface snow if you find yourself on sun exposed slopes during extended sunbreaks.

Weather and Snowpack

The latest of several warm, wet SW streams of moisture this season arrived Valentine's Day 2/14 through Thursday 2/16 along the Cascade east slopes. An avalanche cycle occurred a week ago Wednesday night in the northeast zone and Thursday for lower slopes and areas further east of the crest in the central-east zone. 

In the northeast zone the NWAC station at Washington Pass received about 10-14 inches of moist snow over a thin freezing-rain crust formed early in the storm cycle.  In the central-east and southeast zones, light rain likely reached up about 5-6000 feet in the central-east and up to about 7000 feet in the southeast zone. Fair and sunny weather on Friday, 2/17 formed a sun crust on solar aspects.

Light amounts of new snow accumulated over the weekend. A low pressure system, tracking across the southern Washington Cascades during the day on Monday deposited a few inches of new snow to the central-east and southeast Cascades. A slight warming trend was observed during the storm Monday.

Light snowfall Tuesday changed to showers in the afternoon.

Sun breaks and a few light snow showers Wednesday amounted to little if any additional snow by Wednesday evening.

Recent Observations

North

The NCMG were out near Washington Pass on Sunday and reported that ski tests on steep features gave no results and that wind slab was generally unreactive. A size 2.5 slab, 1 m x 200 m crown was seen on a north aspect at 7200 feet that probably released after cornice fall on 2/15.

On Monday, the NCMG observed a fresh and large storm slab that was triggered by cornice fall mid-day above treeline in the Hairpin Valley on a NNE aspect near 7000 feet. No other avalanche activity was observed. The slab averaged around 40 cm to the most recent crust.

The most recent reports from the north over the past few days indicate that wind slabs continue to gain strength and storm slabs have settled. Good ski conditions remain, especially in shaded terrain with settling 10-14 inches of recent storm snow over the most recent crust. On solar aspects, one or more thin sun crusts are sandwiched within the recent storm snow, but not adversely affecting the avalanche conditions or the fun factor.   

Central

NWAC observer Tom Curtis was at Jove Peak on Monday and found the recent snow generally bonding well to the Valentine's Day crust. Some previous wind slab was apparent below ridgelines near treeline. The possibility for skier triggered, loose wet avalanches increased around midday during a slight warming trend.

Tom Curtis was in the Blewett Pass area Wednesday and found the recent wind slabs were confined to very isolated terrain features on mostly easterly facing terrain at higher elevations. These slabs remained sensitive to ski trigger, but were very isolated in extent, ranging from 2-8 inches.

Very similar conditions were reported from Mission Ridge Wednesday, with isolated wind slabs of 6-8 inches confined to specific steep terrain features below ridges.  

South

No recent observations.