Our Friends at the Colorado Avalanche Information Center (CAIC) have released the first Statewide Avalanche Conditions notice of the 2010-2011 season.

Don’t forget the third annual Avy Bash at the Riverwalk Center in Breck on November 13.

Statewide Avalanche Conditions


Issued 10/18/2010 8:32 PM by Spencer Logan
See this forecast on-line. Goto your account.
The Colorado Avalanche Information Center is a program within the Department of Natural Resources.
Highlights
It is October 18, 2010. Several rounds of snow have dusted the mountains and anticipation is running high. The CAIC will update the Statewide Forecast as conditions change this fall. The Zone Forecasts will resume in November when conditions warrant. We really appreciate your observations of snow conditions and avalanche activity.
Weather Discussion
If you’re headed into the high country use our Weather Stations by Zone page to check temperatures, wind, and snowfall for the last few days.
Snowpack & Avalanche Discussion
There have been avalanche fatalities and accidents in Colorado every month of the year. There was a series of early season incidents last year, and a fatalityin early November of 2005. Shallow, limited snow is no excuse to ignore avalanche safety. We trot out the phrase every year, but

If there is enough snow to ride there is enough snow to slide.

There are a few ingredients necessary for an avalanche. The first is a slope steep enough to slide. Most avalanches start on slopes steeper than 30 degrees, in the range of black diamond ski runs. Slopes that steep are often the first to fill in as snow drifts into gullies and below ridges. Permanent snowfields are usually sufficiently steep, too.

The next ingredient is a layer of strong over weak snow. This is relative strength, so the strong snow can appear quite soft. It just needs to bond together more than underlying snow. One of the best mechanisms for making strong snow is drifting from wind. The areas with snow deep enough to ride are most likely drifted and have the greatest potential for strong over weak layering.

Weak snow is easy to find in the early season. Thin, shallow snow facets rapidly. Faceted snow consists of big sugary grains that are poorly bonded. You can find the biggest, weakest facets are nearest the ground.

Permanent snowfields, at first glance, have weak over strong layering. They are not avalanche immune because a thin layer of very weak snow tends to form at the base of the recent snow. The old, strong snow is often icy and slick, a perfect surface for fast-running avalanches. The icy old snow makes it hard for a rider tumbling in an avalanche to self-arrest or slow down, and high-speed falls result.

The final ingredient is a trigger to break the weaker snow. A rider makes a very good trigger, overloading the weak snow and causing an avalanche. The stronger slab fractures and flows down hill around the rider. Early season avalanches tend to be small, but tumble a rider over rocks and stumps and cause lots of injuries.

We need to brush up on our avalanche skills as part of our pre-season training. Flip through your favorite avalanche books, or check out some of the online tutorials. Beacon practice is a great way to pass a gray afternoon.Your avalanche gear deserves the same attention you lavish on your skis, board, or sled.

First 2010-2011 CAIC avalanche report.

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