Avalanche Advisory Archive 2016 – 2018

Date Issued:2017-01-24 06:57:37
Primary Trend:2
Primary Probability:3
Primary Likelihood:3
Primary Size:2
Primary Description:

We have seen human triggered windslabs around the region over the last several days. Although these started shallow in nature they have now grown with several centimeters of snow a day over several days with continued 20-40mph winds.

Be aware that all though the bond is strengthening it remains a concern.

Chose your position in the terrain wisely and avoid wind slabs in areas of terrain traps.

Secondary Trend:3
Secondary Probability:8
Secondary Likelihood:2
Secondary Size:2
Secondary Description:

With continued winds for several days around the region and new snow our cornices continue to build.

Be aware that a cornice fall often occurs onto the windslabs that are currently in place adding to the danger of trigger and the size of the slide.

Use caution on ridgeline near cornices.


The National Weather Service Forecasts-

Today- Windy. Rain...mixed with snow early in the morning. little or no snow accumulation. Snow level rising above 1200 feet in the afternoon. Highs around 39. Southeast wind increasing to 30 mph with gusts to 45 mph in the afternoon.

Tonight- Windy. Rain. Lows around 37. Southeast wind to 30 mph with gusts to 45 mph diminishing late.

Wednesday- Rain in the morning, then widespread rain showers in the afternoon. Highs around 40. Southeast wind 10 to 20 mph.

Good morning Juneau. Its nice to see some fresh snow in the mountains even if its a little wet.

This morning Eaglecrest is showing 32 at the base. 28 at powder patch and 27 at the summit. All of this is p from yesterdays low of 25. Mt Roberts is a little warmer showing barely below freezing this morning.

We have seen about .4\" of precipitation around the region over the last 24 hours. This left 3-4\" of new snow.

Winds remain a concern around the region with both Eaglecrest and Mt Roberts showing 20-35mph winds over the last 24 hours... The forecast calls for continued considerable winds for loading our lee slopes.

The last week was quite wet around the region with above freezing temps all the way to our mountain summits at times.

Temperatures cooled four days ago allowing the snowpack to solidify and lock back up. The lower snowpack is strong and stable in place for the most part.

We then received a few centimeters of new snow a day for the last few days all during moderate to considerable windloading.

This new snow is not bonding well in all areas.

Remember we also received a fair amount of wind. Currently Eaglecrest is showing 30-40mph winds which are plenty strong to create windloading and build windslabs.

Over the last several days we have seen weak wind slabs building around the region. These windslab avalanches are likely naturally in areas continuing to load and more than likely for human triggered avalanches if you should venture into the wrong place on the slab.

Be aware that over the last three days human triggered avalanches have been occurring around the region.

This bond should strengthen over time but with continued precipitation every day and continued loading every day it has kept the stress/strain balance fairly neutral.

With weak wind slabs in place that have been human triggered over the last several days, and with winds of 20-40mph in the forecast for the region over the next 24 hours and another 1/2\" of precipitation in the forecast avalanche danger is CONSIDERABLE and will remain so.

Natural avalanches are possible and human triggered avalanches are likely especially in windloaded areas.


Here is a link to a great article written about my highschool friend and President of the American Avalanche Association John Stimberis. John and I used to meet in the spring after every season and climb Mt St Helens in our hometown. It has been an honor to work and grow with him over the years.

This article is titled: How avalanche forecasters use bombs, a howitzer, and an m60 tank to keep us safe.


Forecaster:Tom Mattice