Instead of thinking only about how much snow fell, it is also important to consider the snow that was on the ground prior to a new snowfall. In a thin, early-season snow pack, there is often a steep temperature gradient. A temperature gradient occurs when there is a difference between the temperature of the ground, a fairly constant zero degrees Celsius, and the snow lying above the ground, which, during the winter, will generally tend to be colder than zero.

A temperature gradient in a snow pack promotes the creation of faceted grains of snow. Faceted snow is weak snow that bonds poorly with other snow and is recognizable in a snow pit by its more square and angular shapes.

The temperature gradient is generally from the point of the higher temperature (the ground) upward toward the lower temperature (the air). The critical temperature gradient that promotes formation of faceted grains is 10°C per meter, or 1° per 10 centimeters. Facets may form anywhere within a snow pack where a temperature gradient exists. Often in a thin, early-season pack, these faceted grains form on or near the ground and are commonly referred to as depth hoar.

It is easy to imagine that in a thin, early-season pack, generally there will be a very steep gradient, with the probability of generating some very weak snow. Once a weak layer forms, the danger it presents can be prevalent for a long time, perhaps the entire winter.

Taking these ideas into consideration, it becomes clear that the snow load (new snow, wind deposit, etc.) is often no more important than the layer, or layers, that are present when that load is deposited. However, avalanches do not occur when only one of the above components exist. There must be a slab and there must be a bed surface upon which the slab may slide. A slab can form by the natural settlement or the bonding of snow over time and can become very dense and strong. This is referred to as a hard slab.

When a hard slab forms over weak, faceted snow, the ingredients are present for an incredibly destructive avalanche. When these conditions exist, it is best to avoid backcountry travel in all but the tamest areas. Slabs can also form by wind transporting snow to one general area and essentially compacting that snow into one piece. Wind can produce a very hard slab. This can occur very quickly and can transform a benign powder slope into an area to be avoided in a matter of minutes. Often wind slab is visible to the eye, but more often, such as when high winds precede a storm, wind slab can be hidden by several inches of new snow, making it very difficult to detect. This is when it might be prudent to allow a little time for the slope to adjust to its new load and seek out an area you know to be sheltered from the wind.

Being aware of the prevalent wind direction for the day or days prior will help you find the good, and the safe, skiing. Skiing safely through avalanche terrain is not about "getting away" with skiing prone terrain when a hazard exists, but rather knowing how to recognize a hazard and avoid it altogether.

What makes the early season interesting from an avalanche forecaster's standpoint is the same thing that makes it so dangerous from a skier's; there are just so many factors at work. There will be weak snow due to cold temperatures and a thin snow pack, there will be storms (hopefully) that will bring new snow and wind, and slabs will form. Things change more rapidly than they seem to later in the year. It is sometimes very difficult — or impossible — to understand all of the dynamics at work in the snow pack. Expect to be perplexed. I know I often am.

Luckily you don't have to know it all or be an avalanche guru to ski safely in the backcountry. Don't ski alone, always carry a shovel and wear an avalanche transceiver, always have it turned on and know how to use it, and keep your eyes and ears open.

Most areas in the Western mountain states have avalanche forecasting centers that post daily warnings and hazard assessments in the form of a recorded telephone message. These are often quite detailed and can be very educational. Find out the number and spend the dime. With some basic knowledge of snow, sound travel techniques and most importantly, common sense, you'll get a lot of good turns and travel to some really cool places. You are certain to learn a lot along the way. Don't rely on luck out there, because your luck is sure to run out.

Just remember what the old backcountry skier said, "There are no old, bold backcountry skiers."

— Neal Carroll is a ski patroller at Alta, Utah, and a guide for Valdez Heli-Camps in Valdez, Alaska.

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