Avalanche Forecast
Jan 19th, 2019–Jan 20th, 2019
Alpine
2:
Moderate
The avalanche danger rating in the alpine will be moderate
Treeline
2:
Moderate
The avalanche danger rating at treeline will be moderate
Below Treeline
1:
Low
The avalanche danger rating below treeline will be low
Alpine
2:
Moderate
The avalanche danger rating in the alpine will be moderate
Treeline
2:
Moderate
The avalanche danger rating at treeline will be moderate
Below Treeline
1:
Low
The avalanche danger rating below treeline will be low
Regions: Cascades - West.
The Bottom Line: The recent snow still needs time to stabilize. It remains possible to trigger an avalanche at mid and upper elevations on slopes 35 degrees and steeper. Asses upper snowpack layers carefully before venturing into steeper terrain.
Snow and Avalanche Discussion
Since Thursday, neighboring zones received up to 2.5in of water with snow levels near 4000ft. This translated into 12-18in of snow at mid and upper elevations. At lower elevations, a few inches of wet, heavy snow accumulated, while all rain fell below 3500ft. No avalanches were reported on Saturday. Natural and triggered avalanches were reported Friday. These avalanches broke 1-2ft deep at the old/new interface or just above within new snow layers. Avalanches occurred between 4500-5500ft primarily on northerly aspects. Some avalanches were large enough to bury a person (200ft wide and running 400ft feet downslope) but most avalanches were small. The old snow surface is a firm crust that acted as a productive bed surface. New snow instabilities are of most concern above 4500ft where this old snow surface stayed dry. Below this elevation, the new snow appears to have bonded well to old snow surfaces that remained moist/wet. Cooling temperatures over the next 24 hours will solidify the snowpack at lower elevations.
Avalanche Problems
Storm Slabs
Although avalanche activity is trending down, continue to give the new snow time to stabilize. The most likely place to trigger an avalanche is on northerly aspects above 5000ft on unsupported or convex slopes 35 degrees and steeper. Large avalanches may still be possible to trigger. Storm slabs may become more reactive the higher in elevation you travel. Be careful in upper elevation areas where more snow accumulated, and on leeward slopes where deeper drifts of snow exist. Watch for recent avalanches, shooting cracks and collapses. Seek out small, inconsequential slopes to test the snow before venturing into steeper terrain. Dig down to the January 17th crust layer (buried about 1 foot deep in most locations) and investigate how the new snow layers are bonded. If you find sudden results in hand pits or column tests at the new/old interface or within new snow, seek out lower angled or supported terrain to reduce your chance of triggering an avalanche.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood: Possible
Expected Size: 2 - 2