Gulf of Slides snowpack

By Helon Hoffer | Mount Washington Avalanche Center

Date of Observation: February 2, 2019  1:00 PM
Location of Observation: Sandbox and Gully#1

We toured to about 4500′ into the Sandbox in Gulf of Slides. The surface was a mixed bag of melt/freeze crust, supportable wind slab while skinning, and soft snow. After returning to the first aid cache, we ascended to a similar elevation in Gully#1. Conditions were different with almost no exposed melt/freeze crust. The gully proper was pencil hard wind slab that would not support a boot. Thickness of the pencil hard layer ranged from 10cm to 35cm. A layer of first hard snow was under this slab. Depths to the melt/freeze crust were around 60-80cm. Stability tests performed all failed upon isolation in the first hard snow, but the stiffness of the overlying slab supported a skier’s weight, highlighting the bridging strength of the existing wind slab. We observed no cracking while moving through terrain and also observed no signs of recent avalanche activity anywhere in the Gulf of Slides. The main photo is of Gully#1 while the accompanying photos are from the Sandbox, though it was quite windy at the time.


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.


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