YESTERDAY:
2240 meters -11, Winds were 55-75 KPH SE--Horstman Hut
1860 meters -8, Winds were 20-40 KPH SE --Rendezvous
1560 meters -6, Trace in 12 Hrs, 24 cm in 24 Hrs, Base 167 cm--Catskinner
FORECAST:
A short lived break early this am before a warm front arrives on shore with light precip in a Westerly flow aloft. A trailing cold front will bring moderate precip by this afternoon with the FL rising from surface to around 1000 meters with strong winds. Wednesday will be unsettled with mostly overcast skies with some sunny breaks. Thursday will see a weak shortwave ridge build with mostly unsettled weather, mix of sun and cloud. Yet another weak front arrives Friday with some periods of light precip but mostly dry unsettled weather with a good chance of a few breaks. Next significant front will arrive next Tuesday. Guesstimates: 25-35 cm by Wednesday am, 1-3 cm by Thursday am, 0 cm by Friday am, 4-5 cm by Saturday am.
AVALANCHE ACTIVITY:
From Sea to Sky Avalanche Advisory:
Avalanche Summary
A large, natural storm slab avalanche cycle size 3-4 occurred near Pemberton over the weekend. Natural and explosive triggered storm slabs size 1-2 were reported elsewhere. This MIN report from Friday illustrates the active avalanche conditions during this storm.
Persistent slab avalanche activity has tapered significantly since the cycle early last week, but persistent slabs size 2-2.5 were still triggerable by explosives on weekend. Events from last week include:
- A fatal avalanche in the South Coast Inland region (near the Sea to Sky boundary) north of Pemberton in the Railroad Pass area last Monday. It was reported to be a size 2 persistent slab avalanche on a west aspect, around 1650 m. The RCMP press release can be viewed here, and the Avalanche Canada report can be found here.
- A size 2.5 avalanche was triggered on Monday by a skier on Rainbow Mountain, which resulted in a full burial and, thankfully, a successful rescue. The avalanche failed on a 60 cm deep crust and facet layer on a northeast aspect around 1800 m.
These avalanches highlight the ongoing potential to trigger persistent weak layers in the snowpack.
Snowpack Summary
Over 100 cm of recent storm snow has seen extensive wind effect at upper elevations, with scoured windward aspects, wind slabs in lee features and growing cornices at ridgetop.
The snowpack is currently quite complex. The layer of greatest concern is a melt-freeze crust from early December, found around 100-200 cm deep in the snowpack. This crust may have surface hoar or sugary faceted grains sitting above it. There have been several recent large natural and human triggered avalanches on this layer and new snow loads as well as large loads from storm slab avalanches have potential to trigger these layers.
INFORMATION & OBSERVATIONS:


LOCAL AVALANCHE CANADA MIN REPORTS:
No new reports as of 07:00 Hrs this am.
VIDEOS:
Powder Picker Jan 4, 2021: David Jones
ARTICLES:
Mountain Conditions Roundup-Jan 4, 2021: Powder Cloud
Close call for snowmobilers highlights regional avalanche danger: Washington State
Skier dies in wooded area at Big White-Tree Well? would be nice to know!!!: Global News
Snowfall warning issued for: Whistler
Yet another storm brings heavy rain and strong winds to: B.C.
No comments:
Post a comment