Powder: the elusive holy grail of snowsports. Though it may seem hard to find, it actually isn’t if you know where to look! This article will lay out the tools and knowledge you need to be a competent powder chaser.
Note: techniques in this article are meant to be used within the patrolled ski area boundary. Backcountry use of these techniques may lead to dangerous situations and even death.
Big picture: where will the snow be?
This is pretty easy. All you need to do is find an accurate forecast to figure out what resorts will receive the most snow. If you can access more than one resort, this is great. Even in a 50-mile radius, some resorts may receive 5x the snow amount as another, so figuring out which resorts will have big dumps is crucial.
Big picture forecasting sites work well for this first step. A personal favorite service of mine is Windy. It’s relatively easy to use, and you can figure out which resorts are forecasted to receive large snowfall. This step should be conducted 3-5 days before the ski day. 3-5 day forecasts really start to get accurate, 5-7 day forecasts can indicate general storm patterns (i.e., if there will be big snowfall vs. small, what resorts might be good, etc.) but aren’t good at nailing down specifics, and anything beyond a week or so generally only tell you if there will be a storm or not.
The key to success: the aspect game
Playing “the aspect game” is one of the trickiest but rewarding things about localized snow forecasting. There are two key pieces of data that you need to play this rewarding game: sun and wind exposure.
Let’s start with the wind, arguably the biggest determining factor of a good powder day or a mediocre one. First, find a forecast for wind direction. This can be found by right-clicking on a point in Windy, then selecting “Forecast for this location.” Another great resource for more detailed and tabular data is SpotWX.
Once you have this data, you need to find the wind direction. Once you’ve found it, you can use it to your advantage to find good snow. I’ll use an example to illustrate how one might do so:
Let’s say I checked Windy and found that tonight the wind was blowing in a straight westerly (from west to east) flow. That means that during the night, the wind will transport snow from west to east. Generally speaking, ridges and other features will shelter slopes, so behind a ridge, the wind will suddenly stop transporting snow and deposit it on the ground. In the morning, I’ll instantly go to east-facing slopes behind protected features, like a cornice, ridgetop, etc. This is where the wind has deposited snow, known as “wind loading.”
A couple of good rules of thumb when predicting wind loading: my general rule of thumb is that wind can fluctuate about 45 degrees to each side when blowing snow. This means that a wind blowing directly from west to east may also load up northeast and southeast slopes with snow. Wind gusts generally need to be 20mph or more to transport most types of snow. The only exception is super light snow with an SWE ratio of 20-1 or more, which be transported by winds that are weaker than 20mph.
The other thing to keep in mind when playing the aspect game is to keep sun exposure in mind. On a sunny winter day, the sun will hit the southeast slopes first. These slopes will be the first to become mashed potatoey snow, which is not fun to ski, so if you ski any SE-SW slopes, ski them early in the morning. North facing slopes will stay powdery the longest.
Just because a slope is within the patrolled ski area boundary does not mean that avalanches cannot occur. Wind loading, while it can deliver some fantastic snow, is also very problematic for avalanche risk. On snowy days, skiing with a beacon is never a bad idea. ALWAYS ski with a partner. Have fun, but also assess risk as you go.