New wind slabs and avalanche activity

By Ryan Matz | MWAC

Date of Observation: February 22, 2019  12:30 PM
Location of Observation: Tuckerman Ravine

Relatively firm (1F-4F hardness) new wind slab on the surface with variable scouring to older surface. These new slabs were over a slightly softer and less cohesive layer, providing a structure conducive to instability, but this new layer was generally stubborn under skis and boots, with minimal cracking or collapsing.
We observed wind eroded avalanche debris below Left Gully and low in Hillman’s Highway, from suspected natural avalanches late yesterday or last night.
All pictured avalanche paths are truly as well developed and connected as they seem. Between this well developed state and the number of wind slab layers formed in the past week, it’s a great time to respect the low probability and high consequence avalanches that our stubborn firm wind slabs can produce.


Snowpack observations are one part of the complex puzzle which is your decision to enter avalanche terrain. Some observations may include stability tests. It’s important to understand that the results of a stability tests are seldom conclusive anywhere, but particularly in snow climates and terrain like ours where the primary driver of instabilities is wind drifted snow. Many stability tests exist and each works best with specific avalanche problem types. Stability test results should never be used alone as an indication that a slope or conditions are safe particularly when more obvious red flags are present. Please use this page as part of your information gathering process, but don’t make decisions based on a single piece of information. A good article that summarizes some of the issues associated with snow and avalanche observations can be found here.

The Mount Washington Avalanche Center cannot verify the quality or accuracy of any observations that come from the general public.


See an avalanche or evidence of previous avalanche activity?  Near-miss? Snowpack observations?

Your observations are valuable to an accurate forecast! We welcome observations from everyone. You don’t need to be an avalanche professional to submit helpful observations, just be as detailed and accurate as you can.