Observation: NWAC Forecaster

All Observations

Basic Information

Observation Details

Observation Date:
February 25, 2022
Submitted:
February 25, 2022
Observer:
NWAC Forecaster - Matt Primomo
Zone or Region:
Stevens Pass
Location:
Arrowhead (W-N-NE 2,600-5,800. SE-S 5,400-5,700)

Signs of Unstable Snow

Recent Avalanches? 
Yes
Cracking? 
None Experienced
Collapsing? 
None Experienced

Media/Attachments

Large feathers on N aspect at 4,000ft.
WNW aspect at 5,400ft on Arrowhead.
Large, decomposing fragments of stellars with facets and surface hoar growth were widespread. This was from a WNW aspect at 5,400ft.
SE aspect at 5,500ft on Arrowhead. Surface hoar and surface facets likely didn't melt all the way during the day.
N aspect at 5,600ft on Arrowhead, with a crumbly, faceted crust down about 30cm.
Older slab, with recent loose wet slides. West Camp Path above Berne and Hwy 2.
Small loose wet avalanches below treeline on WSW aspects in Whitepine Creek.
Older slab avalanche off a SE aspect of Jim Hill.
Older slab avalanche off a SE aspect of Jove Peak.
Sluffing on NE aspects of Big Chief Mtn.
Glide crack opening on an E aspect of Big Chief Mtn.
Small loose slides off SE and S aspects of Rock Mtn.

Advanced Information

Weather Summary

Cloud Cover:
Clear
Wind:
Calm

Today was a beautiful cold, clear, and still day. The sun felt fairly strong.

Avalanche Observations

 #  Date Location Size Type Bed Sfc Depth Trigger Photos Details
1 Feb 22, 2022
() 		Rock Mountin - West Camp Path
SE 6000ft 		D2 SS-Soft Slab 1.5ft NL-Loose Snow avalanche
Older slab, with recent loose wet slides. West Camp Path above Berne and Hwy 2.
Report
Rock Mountin - West Camp Path

Widespread loose avalanches on SE-SW aspects from yesterday and today, to D1.5. These were mainly on the steep S facing Camp Avalanche Paths off the S side of Rock Mtn, but I observed a few off some WSW facing terrain BTL in Whitepine Creek.

We were able to get some small, loose dry sluffs moving on very steep north facing terrain. These were light and mostly harmless, but worth considering as we descended.

Snowpack Observations

The big takeaway from the day is that recent weather conditions have been just about perfect for surface faceting and surface hoar formation where we traveled.

Surface: We found widespread surface hoar from 5-10mm from valley bottom to summit on W-N-NE aspects. Near surface faceting accompanied these large feathers. On S-SE aspects in the mid 5,000ft range, large surface hoar and facets sat on top of, and beneath a suncrust, which was a 2-3cm thick, friable crust. The sun crust was ~2-4cm beneath the surface.

Mid pack: In the BTL and under canopy, there is minimal new snow over recent crusts, which are stout to impenetrable. Out in the open and at higher elevations we found anywhere from 20-45cm of recent snow over the Feb 18th, and Valentines Crust layers. On South aspects, and areas with less than ~30cm in the shade, the recent storm snow has faceted out, down to thicker crust.
On NW-N aspects the Valentines crust was thinner, more crumbly and weaker.

Generally great travel, though quite slippery on the skin track. Excellent recycled powder skiing. Still hitting some ice chunks and debris esp below 4,500ft.

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