Friday, April 20, 2012

The Cottonwoods Are Utah's Powder Shangri-La

"Skiers will eventually find that the Brighton Basin, or the heads of the [Cottonwood] canyons within a short radius of this winter paradise, offer the best skiing to be found in the Wasatch Mountains."
- S. D. Green, U.S. Weather Bureau Meteorologist, 1935

Today we conclude our discussions of the snow climates of northern Utah by answering a question that I am frequently asked.  Is there a place in Utah with a better climate for deep-powder skiing than the Cottonwood Canyons?

No.  Or maybe better put given the uncertainties, probably not.  

The S. D. Green quote above pretty much sums up the situation.  Green was the original Wasatch Weather Weenie, a meteorologist and an avid backcountry skier.  Some of his photographs are part of the ski archives in the University of Utah Marriott Library.  He and the early ski pioneers recognized pretty quickly that there was something special in the upper Cottonwood Canyons.  

S. D. Green photo of skiers near the Wasatch Mountain Club lodge,
Brighton, UT.
We'll answer the question by looking at the available data.  Since extensive snowfall observations are not collected throughout the Wasatch, we'll rely on the PRISM digital precipitation analyses produced by Oregon State University and SNOTEL observations.  

The PRISM analyses suggest that the annual precipitation in the mountainous areas of northern Utah is greatest in two areas.  One is in the Cottonwood Canyons (southernmost red box), the other is on Ben Lomond Peak in the northern Wasatch (northernmost red box).  

Average annual precipitation (inches) in the mountainous regions
of northern Utah.  Source: PRISM Climate Group, Oregon State University 
This analysis is of course not perfect.  It doesn't fully resolve terrain effects and their are data gaps, but we can say that it is likely that the Cottonwoods and Ben Lomond Peak (and adjoining Willard Peak) are the wettest locations in northern Utah.  Further, while this is annual precipitation, most of the precipitation that falls over our mountains falls during the cool season.  At Alta, for example, 70% of the precipitation falls from November to April.  Therefore, the spatial pattern in the mountains above is strongly influenced by precipitation during the cool season.

Next, we'll bore into the climatology of the Cottonwoods and Ben Lomond.  I'm going to use SNOTEL data, which isn't perfect, but should suffice.  At the Snowbird SNOTEL, the snowpack SWE peaks at about 44", whereas at the Ben Lomond SNOTEL, it peaks at about 40".  

Source: Colorado Basin River Forecast Center
The data periods at these two sites are, however, different (Ben Lomond goes back to 1979, but Snowbird only back to 1990), so this is a bit of an apples and oranges comparison.  In addition, the Ben Lomond site is located at only 8000 feet, compared to 9640 feet for Snowbird.  Nevertheless, the evidence suggests that Ben Lomond is a fairly snowy place, and, at a given elevation, possibly as snowy or even snowier than the Cottonwood Canyons.  I have taken groups of students up Ben Lomond during the spring and the snowpack near the SNOTEL site is usually quite impressive.  I call it "pound for pound the snowiest place in Utah", which means for its elevation, it is the champ.

But, Ben Lomond is not the undiscovered deep-powder Shangri-La for a few reasons.  First, it only reaches to 9700 feet.  The terrain around the Cottonwoods is higher, reaching over 11,000 feet in places), which helps make up for contrasts in precipitation at a given elevation and results in a colder climate that better preserves powder.  Second, the storms at Ben Lomond are typically monsters that occur during southwesterly flow.  This gives a big snowpack, but often creates high avalanche hazard and is not optimal for a high frequency of powder days.  Finally, I've skied on Ben Lomond many times and it is an extremely windy place on the ridge and above timberline.  Finding good powder in the alpine requires good fortune.  

Thus, while there is good skiing to be had throughout northern Utah's mountains, the closest thing to powder Shangri-La really is the Cottonwood Canyons.  As Don Henley sang for the Eagles in The Last Resort, "there are no more new frontiers, we have got to make it here."  


  1. Thanks for the fascinating post! Climatology comparisons like this are my favorite.

  2. I obviously agree with your assessment, but have one big bone to pick: the Cottonwoods are too darn crowded! I'll take an undiscovered place that averages 350" over a crowded place that averages 500".

    1. Indeed Todd, and the recreational pressure in the Cottonwoods will likely grow as the population along the Wasatch Front increases.

  3. So where do i open my new resort

    1. There are enough ski areas in the Wasatch. Try Buffalo Pass, CO.

    2. There's always room for one more.

  4. Why stop at the Cottonwoods? Care to pin it down further? Which bowl in the Cottonwoods has the very best snowpack? Let's define this by the deepest bowl-averaged snowpack in areas without much wind drifting. Of course, this would probably end up being a north/northeast facing bowl. Would it be closer to Wolverine, or further west like around White/Red Baldy or Dromedary/Twin Peaks?

    1. Send me some funding Todd and I'll get on this right away....