Hatcher Pass Avalanche Center
Hatcher Pass

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Issued
Thu, February 4th, 2021 - 7:00AM
Expires
Fri, February 5th, 2021 - 7:00AM
Forecaster
Jake Kayes
Conditions Summary

Today’s avalanche problem will be dry loose avalanches. Human triggered avalanches are possible at mid and upper elevations on all aspects. These avalanches will be small in size. Natural avalanches are unlikely.

Riding quality has improved and low density snow is plentiful. That being said coverage is still thin especially near ridge tops. While coverage is improving, rocks and other hazards are sitting just below the surface. Even a small avalanche could have high consequences involving these hazards.

Recent Avalanches

There have been multiple human triggered dry loose avalanches this week.

There was also one very small wind slab triggered on 12/3 on Marmot SW 4000’. For more info click here.

A small wind slab and dry loose on Marmot 4000′ SW

Avalanche Problem 1
  • Dry Loose
    Dry Loose
  • Certain
    Very Likely
    Likely
    Possible
    Unlikely
    Likelihood
  • Historic (D4-5)
    Very Large (D3)
    Large (D2)
    Small (D1)
    Size
Dry Loose
Dry Loose avalanches are the release of dry unconsolidated snow and typically occur within layers of soft snow near the surface of the snowpack. These avalanches start at a point and entrain snow as they move downhill, forming a fan-shaped avalanche. Other names for loose-dry avalanches include point-release avalanches or sluffs.
Likelihood of Avalanches
Terms such as "unlikely", "likely", and "certain" are used to define the scale, with the chance of triggering or observing avalanches increasing as we move up the scale. For our purposes, "Unlikely" means that few avalanches could be triggered in avalanche terrain and natural avalanches are not expected. "Certain" means that humans will be able to trigger avalanches on many slopes, and natural avalanches are expected.
Size of Avalanches
Avalanche size is defined by the largest potential avalanche, or expected range of sizes related to the problem in question. Assigned size is a qualitative estimate based on the destructive classification system and requires specialists to estimate the harm avalanches may cause to hypothetical objects located in the avalanche track (AAA 2016, CAA 2014). Under this schema, "Small" avalanches are not large enough to bury humans and are relatively harmless unless they carry people over cliffs or through trees or rocks. Moving up the scale, avalanches become "Large" enough to bury, injure, or kill people. "Very Large" avalanches may bury or destroy vehicles or houses, and "Historic" avalanches are massive events capable of altering the landscape.

Signal Word Size (D scale) Simple Descriptor
Small 1 Unlikely to bury a person
Large 2 Can bury a person
Very Large 3 Can destroy a house
Historic 4 & 5 Can destroy part or all of a village
More info at Avalanche.org

6-8” of new snow and cold temps have created snow surfaces that are very low in density. This low density snow will be capable of producing dry loose avalanches at mid and upper elevations and on all aspects. This avalanche problem will be found in terrain 40° or steeper. Human triggered avalanches are possible and will be small in size. Natural avalanches are unlikely.

These dry loose avalanches will be able to gain mass and speed rapidly. Some may entrain older, sugary faceted snow which will increase the volume of sluffs. It will be important to practice good sluff management when stepping out into steeper terrain. While these avalanches will be small, they will be able to catch, carry, and sweep you into hazards such as rocks, cliffs, and terrain traps if not managed properly.

Eldorado Bowl- While coverage is improving rocks are sitting just below the surface

Small cracks on cornices on Marmot Ridge

Weather
Thu, February 4th, 2021

New snow totals 1/31-2/4: 

Independence Mine 6-8”

This week Hatcher Pass saw cold temperatures, strong winds and 6-8” of new snow. At the start of the week sub zero temperatures dominated the weather stations, with lows of -2°F. As the week progressed temperatures began to rise. With this rise in temperatures we also had a short strong wind event on 2/2. These winds were strong and from the east but only lasted for 5 hours. On feb 3rd 6-8” of low density snow fell at independence mine station.

NWS Rec Forecast here.

NWS point forecast here.

State Parks Snow Report and Motorized Access information here.

Independence Mine 1/31-2/4:

Marmot 1/31-2/4:

Observations
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