We all know that in this great big world of ours, there are seasons, and that things like weather and local conditions change from day to day, week to week, and of course month to month. But how do these changes in the season affect the mountains and our travels in them. For most people, the mountains are the glittering points on the horizon. Sometimes they are snowy, sometimes they are bare, sometimes you can see them, but most of the time you can't. So what is going on up there anyhow? Being both a guide and a Program Coordinator in AAI’s offices, I often field questions about courses and programs that are “out of season” so to speak. Quite often people wonder why we don’t offer particular courses and climbs year round. A simple answer would be, the seasonality of mountaineering.
Most ranges of mountains have a defined or “typical” mountaineering season. That is to say a season where the climbing conditions are optimal for the types of climbing contained therein. Each range and place is unique in its characteristics, patterns, and factors, but there are many similarities as well. I will use the Cascade Range here in Washington as a model.
My first few years as a new climber in the Cascades were frustrating to say the least. I didn’t have much of a feel for conditions in the mountains, where to find info on such things, or how to interpret lowland factors to extrapolate highland realities. Many of my trips were met with bad weather, too much snow, not enough snow, or the route being “out of condition” for any number of reasons. Now, after over a decade of running around in the Cascades, I can almost predict the exact conditions at any given time without having been in the range for weeks or even months. This isn’t accomplished by any special skill in particular, but more from being familiar with the seasonal changes that happen every year, by knowing how to interpret lowland factors, and by knowing where to look for up to date information. Being familiar with each of these relatively straight forward process can help your success rate and enjoyment factor go way up by minimizing some of what is typically thought of as guess work in mountaineering.
The glacier mountaineering season in the Cascades is generally thought of as the summer months. Conditions for glacier climbing are at their best when the snowpack has gone isothermal and the surface of the glacier freezes at higher elevations during the night. During this freeze, climbers wear boots and crampons and walk on top of the snow instead of sinking into it deeply like they do during the winter and early spring months. Conditions in the mountains are always changing. Sometimes they are literally different from one minute to the next. Being able to predict, plan for, and properly assess these conditions can make a huge difference in your level of success, enjoyment, and even safety.
For the sake of order, lets look at the seasons starting from the end of the summer, before the snow starts to fall. Since many of these concepts revolve around snow, it makes the most sense to start from the beginning when there is none. Here in the Cascades, the middle or even the end of September is the end of the typical mountaineering season. Depending on the year, we might get some decent weather into October and be able to sneak in another climb or two, but the days are short and the snow can fly at any time.
As I write this I can see our last Cascade mountaineering group out my rain-streaked window returning from Mount Baker where they got pummeled by rain and snow. By the end of our summer, nearly all of the seasonal snow has melted off the surface of the glaciers and from the lower and even higher elevation slopes. When the snow starts again, it will gradually (or rapidly depending on the storm!) accumulate throughout the winter, usually into March when the days become long enough and bright enough that the snow pack depth starts to even out and even recede despite the fact that new snow is still falling regularly.
To Read Part II, Click Here.