Quick report
Met up with an old friend today to spend a soggy day in GNP. Good company made for an enjoyable outing and was the perfect distraction from all of the snowless travel below 5000 feet. We went up to Mount Brown Lookout for a pulse check on the Persistent Slab problem and to see how much new snow has fallen on the places that are fortunate to live above the recent rain line. We found intact surface hoar at the mid-February interface, as well as at the January Drought layer. The JDL weak layer is 60cm below the surface and held very large (10-20mm) surface hoar that produced propagating results in two ECTs. The slab dropped with a good amount of energy and I suspect it would have slid into our pit if we had been digging on a steeper slope. The overlying slab is stiffening over time, and the fact that it is still producing energetic propagation more than a month after burial is pretty scary. none observed
Weather
- Cloud Cover
- overcast
- Wind Loading
- none
- Rain Elevation
- 4800 - 6000
- Recent Snowfall
- 16cm
- Snow Avail For Transport
- small smounts
Cloudy moist day. Rain/snow line started at 4800 in the morning and climbed up towards 6000 feet later in the day. Winds were light out of the southwest.
Snowpack
On-the-go observations: • No snowpack exists on the summer trail below 5000 feet (sadly) • Precipitation within the last 72 hours has left only liquid below 4800 feet. Trace accumulations of new snow start there and work up towards 6 to 7 inches near the lookout (7400 feet) • The recent snow has fallen on top of a stout (pencil hard) supportable crust on southerly slopes • Winds today were mostly light out of the southwest. • The new snow is pretty dense and might not easily transport as winds pick up tonight/tomorrow. Details from our pit site, 7400' NE aspect: • HS- 255cm • Mid February PWL- 5-10mm Surface Hoar. Down 50cm. No failure on ECTs • January Drought PWL- 10-20mm Surface Hoar. Down 60cm. ECTP14 and ECTP19 • The 60cm slab that overlays the JDL is transitioning to becoming a proper Hard Slab, even at this sheltered NE facing pit site. Upper half of the slab is 4F hard and the lower half is 1F hard. • The upper 6-7 inches of recent snow has a thin breakable mid-storm lens (freezing rain or rime crust) a few inches below the surface. This might become a good failure plane for any additional storm snow in the coming days.