Avalanche Advisory Archive 2016 – 2018

Date Issued:2017-03-24 07:08:23
Primary Trend:2
Primary Probability:4
Primary Likelihood:3
Primary Size:2
Primary Description:

The persistent weak layer deep in the snowpack still remains the primary concern.

This weak layer has shown to be easily human triggered for a period of over a week now.

It has also been avalanching naturally in places with little for a trigger mechanism.

Secondary Trend:1
Secondary Probability:6
Secondary Likelihood:3
Secondary Size:2
Secondary Description:

Be aware if we see much in the way of sunlight today our avalanche danger will rise throughout the heat of the day.

From mid to late afternoon South to SW facing slopes should be avoided in avalanche terrain.

If we dont see much sun activity will remain limited.

Yet if we do see much activity from wet loose avalanches its important to recognize with the current weakness deeper in the snowpack these small wet loose slides can te the trigger for a much deeper larger slide. I dont expect to see large wet loose avalanches... but I do feel those small wet loose avalanches could easily start that deeper larger slide.

Use extra caution for that reason in avalanche prone areas during the afternoon.


The National Weather Service Forecasts-

Today- Mostly cloudy. Patchy freezing fog early in the morning. Slight chance of rain in the afternoon. Highs around 41. North wind 10 mph.

Tonight- Snow and rain likely. Snow accumulation to 1 inch. Lows around 31. Northwest wind 10 mph.

Saturday- Snow and rain. Snow accumulation to 1 inch. Snow level 400 feet. Highs around 39. Light winds becoming southeast 10 mph in the afternoon.

Good morning Juneau. The weakness still remains within the snowpack around our region. I continue to hear reports of both natural and human triggered avalanches.

Folks these are not small... we have had a few close calls out there in the last week. Please be aware this lingering danger could remain present for some time.

Temperatures on Douglas Island cooled a bit in the last 24 hours. Eaglecrest is showing 24f while the Mt Roberts Tram along the channel is showing 31f. Still below freezing but barely.

We picked up a little new snow with Eaglecrest showing 4cm and the tram with 5cm (2\"). This new snow will be easily wind transported and actually much of it came in with winds of 15-35mph out of the SE.

We will see weak windslabs in places yet most of those should remain shallow. Be aware these may also weight a slope with the deeper instability in place which could turn a small windslab into the trigger for a very large slide.

This will continue to stress the weak layer in place and keep it closer to a state of failure.

The forecast for today calls for some additional warming to where we will see above freezing temps in some of our lower mountain starting zones again. This may be enough to start small point loose avalanches...

If we see much sunshine be aware this will greatly affect stability during the middle to later part of the day. The solar radiation erodes bonds in the snowpack quickly.

It hasn't taken much lately to start avalanches... even a small wet loose slide has been more than enough to trigger slopes to the deeper persistent weak slabs in place.

With natural avalanches possible and human triggered avalanches likely avalanche danger remains CONSIDERABLE today.

Be careful out there folks. Choose your terrain wisely.


Here is a link to a paper on the propagation saw test.

This is a great test to learn and have in your avalanche assessment tool bag.


Forecaster:Tom Mattice