Turnagain Pass

Yesterday was our first chance in just over a week for a dose of fresh snow to cover the plethora of old tracks. We did get enough to do so in some locations but not quite enough in others. Most stations are reporting around 5-6” of low desnity snow (thanks to our cold temperatures) in the past 24 hours. A bit more can be expected at the higher elevations as well as in favored areas such as the northern side of Turnagain Pass and the Girdwood Valley.

Winds associated with yesterday’s snow were moderate from the east and having an easy time blowing the light snow into shallow drifts and soft slabs. This wind deposited snow has covered up all types of old surfaces such as sun crusts, wind crusts, old wind slabs and near surface facets (old soft powder). All of these surfaces will inhibit good initial bonding of the new snow. Wind slabs today should be soft and in the 4-12” range depending on how much snow fell in the area you are traveling. Watching for wind drifted snow and new snow that cracks out from your sled, board or skis will be the key. Expect any slide triggered on a crust or hard surface to run fast and far.

Additionally, watch for soft slabs in wind sheltered areas. The warming temperatures overnight will cause the loose snow from yesterday to bond forming an upside down layering. This warming will eventually help the new snow to stick to the underlying surfaces but, there is a window where the new snow becomes more reactive first. Keep this in mind in areas with greater amonts of snowfall.

Below is an image of cracking in a small fresh wind slab from yesterday – something to watch for today.

If you are traveling in the Summit Lake area old wind slabs are a concern. Check out the Summit Advisory as well as Fitz and Kevin’s observation from yesterday.

Any new snow will easily slide on the old surfaces – especially where a crust sits underneath. Triggering a sluff is most concerning where new snow amounts are ~6” or greater.

Additional Concerns:
Don’t forget about steering clear of looming cornices. The temperature has gone up significantly in the past 24 hours at the upper ridgetops and this will increase the likelihood of cornice failures.

Surface Conditions:
Needless to say, the surface conditions are a bit variable with scoured areas alongside soft wind drifts. The best riding is likely in wind sheltered locations where a few inches of new snow on a crust or soft old snow can be found.