Quick report
Took advantage of the blue skies and good weather to get into the high country a bit and gain more information about NTL and ATL terrain. We've had limited data from this elevation band thus far this season as it has been hard to access with minimal snow and the nature of our avalanche problems.
Lots of avalanche activity observed, likely from the 1/22 storm. Wind affect was more specific, debatably isolated in this area. Certain slopes were heavily affected and some not at all. For the first time this season, we observed avalanche activity on SE slopes ATL (dry loose).
Avalanches included wind slabs, dry loose, and persistent slabs. Sometimes, surface instabilities stepped down to produce persistent slabs. Size varied, and was limited by the nature of complex, rocky terrain in this area, and ground anchors. Even on predominately S facing slopes, which have minimal snow coverage, small E - N features had recent avalanche activity. I intentionally stuck to low angled terrain, clear of overhead hazard.
No cracking or collapsing observed, personally, but I was able to trigger sluffing. Only collapsing observed was breaking through developing MFcr on the surface of solars to colder snow beneath later in the day. Dozens of avalanches observed - PS, WS, and Dry Loose. Mostly E - N aspects, NTL, and ATL.Weather
- Cloud Cover
- few
- Recent Snowfall
- 25 - 35 cm
- Snow Avail For Transport
- large amounts
Cold morning (28º F) with blue skies and minimal wind. Temps rose quickly, especially at lower elevations and in direct sunshine. By early afternoon, light NW winds were picking up, and temperatures dropped significantly with increasing elevation.
Snowpack
Snowpack varies by aspect and elevation here. Overall, the 25 - 40 cm of new snow is not bonding well to the variety of surfaces it fell on (MFcr, wind slab, ground, etc.). And, we are still very concerned with the Depth Hoar at the base of our snowpack, as it is extremely well developed and reactive in this area.
N BTL - 9800', protected slope, no wind loading observed, sluffing and very inconsistent localized collapsing whilst breaking trail, HS observed 90 -130 cm, HST 15 - 35 cm, 20 cm Depth Hoar @ bottom of snowpack. Upside down snowpack. See pit # 1 below.
E BTL - 9700', wind loading variable, HS observed up to 135, HST 30 cm, various crusts, 50 cm of facets/Depth Hoar @ bottom of snowpack. See pit #2 below.
ENE NTL - 10200', wind affect present, HS observed ~ 65 cm, HST ~ 30 cm, ~20 cm Depth Hoar @ bottom of snowpack. ECTP13 @ ground, PST 25/100 END. See pit # 3 below.