Avalanche Advisory Archive 2016 – 2018

Date Issued:2017-03-27 08:50:13
Primary Trend:1
Primary Probability:2
Primary Likelihood:2
Primary Size:1
Primary Description:

Be aware that the 15-20cm of new snoe over the weekend created some new weakness in the region. Mostly shallow and yet reactive in places yesterday.

I was able to release several small slides in the top 15-20cm of the new snow yesterday.

Secondary Trend:2
Secondary Probability:4
Secondary Likelihood:2
Secondary Size:2
Secondary Description:

The deeper persistent weak layer in the region remains in places. Although the slab is stiffening and the liklihood of this event is deminishing the consequence remains high with a harder slab in most places now.

This deeper weak layer could see activity as much as a meter deep in places.

Be aware and be conservative unless you have done the research to know a slope doesnt have this weakness.


The National Weather Service Forecasts-

Today- Snow likely early in the morning, then rain. Little to no snow accumulation. Snow level 500 feet in the morning. Highs around 44. Southeast wind 10 mph.

Tonight- Rain. Widespread rain and snow showers late. No snow accumulation. Snow level 1300 feet late. Lows around 35. Southeast wind 10 mph in the evening becoming light and variable.

Tuesday- Snow likely in the morning. Rain likely . No snow accumulation. Highs around 43. Light winds.

Good morning Juneau. Temps are very near the freezing point today after spending most of yesterday at or above freezing. This am Mt Roberts is just below 32f. Eaglecrest is 32f at the base. 31f mid mountain and 29f on top.

Winds are mild this am with Eaglecrest showing E 10-12... and Mt Roberts at NNE 5-7mph.

The little bit of new snow we picked up Friday into Saturday and again Saturday into last night created some interesting weakness in places yesterday in the top 15-20cm of the snow.

I had very weak test results and saw a few small slides pull out on this near surface instability.

The forecast for today calls for very little warming. Light winds and less than 1/2\" of precip in the next 24. This should not change conditions to much.

With a weak shallow surface slab in places... and another .5\" of precip with very slight warming over the next 24 hours avalanche danger is Moderate today.

Remember we also have a deeper persistent weak layer in places. My tests over the weekend showed that layer gaining strength where I looked... yet we need to keep an eye on it and recognize weakness may remain in the region on this deeper instability.

We could see small natural avalanches if we see much warming... yet activity should remain at a minimum today.

We are very near freezing... if we see more snow than forecast or if we see more warming than forecast we could see additional activity but in general things are fairly stable.

Yet be aware when we add YOU the trigger things may be more considerable in places. There is the weak surface slab... that may be easily triggered... and the underlying weakness that may also be triggered... The first is a small slide... and the second is not likely... yet if you happen to trigger the first and it is big enough to then trigger the deeper weak layer... that would be a bad event...

Be aware out there and use a little extra caution.


Get out and take the time to dig pits. Conduct snow stability tests... Look at the snow... learn from it. Especially when we go through longer periods of instability. It gives you a chance to really see a weak layer and test it over time... seeing it strengthen... telling you when the time is right to push up the slope angle...

Remember... the more you know, the safer the snow... Its a lifetime of learning...

Stay safe out there and be good backcountry partners!

Forecaster:Tom Mattice