Avalanche Advisory Archive 2016 – 2018

Date Issued:2017-03-16 07:28:20
Primary Trend:1
Primary Probability:3
Primary Likelihood:3
Primary Size:2
Primary Description:

With winds from 20-30 and gusting higher over the last 36 hours avalanche danger remains Considerable in the form of windslabs.

Be aware the weak layers were triggering easily even before this wind event added additional weakness to the slab.

Steep windloaded slopes with consequence should still be avoided.

Secondary Trend:1
Secondary Probability:2
Secondary Likelihood:2
Secondary Size:2
Secondary Description:

With 20\" of new over the last 3 dyas sitting on a weak layer storm slab releases are possible as well.

Avoid steep unsupported convex slopes and terrain with increased consequence. These slabs will not be widespread and may be getting harder to trigger and yet the consequence at this point would be significant should you be caught in one of these slides. The size is starting to become an issue.


The National Weather Service Forecasts-

Today- Widespread snow showers in the morning, then scattered snow showers in the afternoon. Snow accumulation to 1 inch. Highs around 35. Northeast wind 10 to 15 mph.

Tonight- Becoming locally windy late. Mostly cloudy. Isolated snow showers. Lows 24 to 32. Northeast wind 10 to 20 mph. Gusts to around 40 mph late near downtown juneau and douglas.

Friday- Cloudy. Locally windy in the morning. Scattered snow showers. Scattered rain showers in the afternoon. Highs around 33. North wind 10 to 20 mph. Near downtown juneau and douglas, gusts to around 40 mph in the morning.

We have had a pretty good 3-4 days of snow. Eaglecrest has seen 50cm of new snow over the last 4 days at about 12% density average after settling. That's a pretty good shot of light dry snow.

Yesterday things warmed up a bit and we had winds from 20-30 on Douglas Island with higher gusts. This light snow transports easily.

This surface warming of the snow during winds has the ability to increase densities in the top portion of the slab rapidly. Both through the warming process and by the windloading process. This can build slabs rapidly that add increased stress to the weak layer in place.

We saw quite a bit of avalanche activity during the first portion of the storm. Both loose snow and soft slab avalanches. That layer has gone somewhat dormant over the last two days and yet its important to remember it showed us its tender heart already...

If you venture into the wrong place today the possibility of human triggered avalanches still exists on this deep weak layer.

The forecast for today calls for light to moderate winds increasing tonight into tomorrow. This will once again add windloading to the equasion.

The snowpack is near a state of imbalance in places. It wont take much to get things moving still on steep convex unsupported slopes. With winds later on or with snow falling off of trees and rocks as the trigger, Natural avalanches remain possible; human-triggered avalanches likely especially in windloaded areas.

Avalanche Danger remains CONSIDERABLE today.

Have an amazing day and yet use a little extra caution and good common sense.


Here is a link to a great article by Bruce Tremper about Quick Snow Stability Tests


Forecaster:Tom Mattice