Avalanche Advisory Archive 2016 – 2018

Date Issued:2017-01-23 06:55:12
Danger:2
Primary Trend:2
Primary Probability:3
Primary Likelihood:4
Primary Size:1
Primary Description:

Keep an eye out for weak cornice formations. Knowing they are probably hanging over the windslabs increases the concern ot their failure.

With this new snow over the last few days and winds these should be fairly trigger sensitive in places.

Secondary Trend:2
Secondary Probability:8
Secondary Likelihood:2
Secondary Size:1
Secondary Description:

Keep an eye out for weak cornice formations. Knowing they are probably hanging over the windslabs increases the concern ot their failure.

With this new snow over the last few days and winds these should be fairly trigger sensitive in places.

Discussion:

The National Weather Service Forecasts-

Rest Of Today- Rain and snow. Snow accumulation to 1 inch. Snow level rising to 700 feet. Highs around 36. Southeast wind 10 to 15 mph in the morning becoming light and variable.

Tonight- Rain and snow likely in the evening. Snow likely late. Snow accumulation to 1 inch. Lows around 32. Southeast wind 10 to 15 mph.

Tuesday- Rain and snow becoming rain in the afternoon. Snow accumulation to 2 inches. Snow level 300 feet increasing to 700 feet in the afternoon. Highs around 36. Southeast wind 10 to 15 mph.

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

Temperatures cooled three 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 two days ago and another 3cm last night.

This new snow is not bonding well in all areas.

We also received a fair amount of wind. Currently Eaglecrest is showing 20-25mph winds which are plenty strong to create windloading and build windslabs.

This new snow is easily transported and we have seen weak wind slabs building around the region. These windslab avalanches are likely both naturally in areas continuing to load and man made if you should venture into the wrong place on the slab.

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

Temperatures have warmed a fair amount over the last 24 hours. This morning Eaglecrest Powder Patch gauge has warmed to 2.4c(28f) from yesterdays low of -5.8c (23f) Mt Roberts is showing 31f this morning. These near freezing temperatures will help the snow bond better to the old snow bed surface over time.

Todays forecast calls for continued light snow and near freezing temps with light to moderate winds.

Although the forecast calls for new snow windloading will remain the primary concern with snow values being quite low over the next 24 hours.

With Natural Avalanche Possible but not likely and Human Triggered Likely Avalanche Danger remains Moderate to Considerable at this time.

Chose your terrain wisely. Think of how the winds lay on the land and imagine where those wind slabs are lurking... Avoid steep covex slopes in windloaded areas and be aware that the base layer is quite hard and icy in places which could turn a very small avalanche into a slide for life situation... These slides will be quite fast right now.

Tip:

Avalanche facts

An avalanche occurs when a layer of snow collapses and slides downhill.

Avalanches are caused by four factors: a steep slope, snow cover, a weak layer in the snow cover and a trigger.

Roads and railway tracks may be rerouted to reduce risks.

Safe avalanches may be triggered in dangerous snow packs.

Avalanches can travel up to 90?km/h.

After one hour, only one in three victims buried in an avalanche is found alive.

The most common causes of death are suffocation, wounds and hypothermia.

Avalanche safety

If you are planning to travel in backcountry, take an avalanche safety course.

When traveling in backcountry, always travel in a group. Ensure you have an experienced group leader. Always stay within view of your group.

When driving, observe the sign \"Avalanche Area-Do Not Stop.\"
Drive carefully in avalanche areas. Avalanches may reach the road without warning.

Obey road closures. When the avalanche hazard is high, control work by explosives may be carried out at any time.

If an avalanche blocks the highway, remain in your vehicle with seat belts on. Wait for assistance. It is easier to find a car in the snow than it is to find a person. Drive to a safe area if possible.

Avoid driving through even small avalanches.

Forecaster:Tom Mattice