Want to feel like an Aspen local? Read this quick overview about Aspen’s geography and weather patterns and you’ll be on your way.
The four resorts of Aspen/Snowmass are located in the northern part of the Elk mountain range of central Colorado. This range has seven peaks over 14,000 feet (locally called “14ers”), and the tallest mountains are to the south and west of Aspen. Remember this; it will be important in a moment.
Understanding the location of mountain ranges is important because big mountains create their own weather. Air is forced to rise over these masses of rock, and as the air rises it cools and moisture condenses into snow. This is called orographic lift and it’s the most important factor when forecasting powder.
If you’re looking at a weather map searching for the next storm heading toward Aspen, keep your eyes out for storms that bring winds from the west. This is by far the best wind direction for Aspen and storms that have a westerly wind can often dump more snow on the ski runs at Aspen than any surrounding ski area.
On the flip side, don’t be fooled by storms with winds from the southwest. While they might sling lots of moisture and clouds toward Aspen, southwest winds actually descend from the tall mountains to the southwest of Aspen (remember where the 14ers are located?). Descending air dries the atmosphere and leads to much less snow.
When favorable winds combine with good moisture and cold temperatures, massive snows can pile up. The most snow ever reported by Aspen in a 24-hour period is 19 inches at both Snowmass and Aspen Highlands. The biggest season recorded in the last 30 years was 2007/2008 when 409 inches fell at Snowmass.
These are big numbers, but where do they come from? Where does Aspen measure snow?
To the delight of the people in charge of snow reporting at Aspen, there is no need to go out on the hill at 430 a.m. Automated snow reporting stations spread around all four resorts report new snow totals and a live person double checks the data before releasing the morning report.
Now that you know the local weather patterns at Aspen and how snow is measured, the only thing left to do is enjoy your powder day!
Joel Gratz is a meteorologist & the founder of OpenSnow.com.