Snowfall in the Deer Valley Expansion Area

Yesterday Deer Valley dropped one of the biggest stories in Utah ski history, announcing plans to add 16 new chairlifts, 3700 acres of terrain, and 135 ski runs in an area including, around, and above the nascent Mayflower resort.  This includes terrain south of the current Jordanelle Gondola and below the Sultan and Mayflower lifts, above the developing Mayflower resort (labeled "new base area" below), and the ridge that extends southward from Bald Mountain toward Heber Valley, including Park Benchmark Peak (9384 ft).  

That is an enormous expansion, but this is a blog about mountain meteorology and snow snobbery, so lets take a look at the meteorology.  

For my book Secrets of the Greatest Snow on Earth, I produced an analysis of mean annual snowfall in the Wasatch Range.  It illustrates what, in the 1930s, meteorologist S. D. Green called the natural advantages of the Cottonwood Canyons.  Snowfall in the high terrain around the Cottonwoods, especially Little Cottonwood, is much greater than it is on and east of the Park city Ridgeline and the Deer Valley area.  

Source: Secrets of the Greatest Snow on Earth, 2nd Edition

In fact, near the bases of Park City Mountain Resort and Deer Valley, snowfall is about 40 to 50 percent lower than found at comparable elevations in Little Cottonwood Canyon.  This is largely a consequence of being on the climatological leeward side of the central Wasatch.  

I've identified the area of the Deer Valley expansion in yellow in the figure above.  Snowfall at the base of the Mayflower area is probably around 150 inches.  The terrain between Jordanelle Gondola and Mayflower and below the base of the Sultan chair probably averages 150 to 200 inches of snow a year, with the highest amounts near the base of the Sultan Chair at just over 7500 feet.  Near the summit of Park Benchmark Peak the averages will probably be a bit over 300 inches.  

The area will be favored in southerly to southeasterly flow storms that favor heavy snowfall in the current Deer Valley Resort.  Probably the best terrain for powder skiing, will be the northeast facing shots off the ridgeline that extends southward and southeastward from Park Benchmark Peak.  Depending on how far south they are going, there could be some northeast and north facing options off of other ridges a bit farther south.  

Map source: CalTopo

Due to the low elevations of much of the terrain, it will be more vulnerable to climate change.  In a warming climate, a greater fraction of precipitation that previously fell as snow will fall at rain at 7000 feet compared to 10,000 feet.  More mid-winter snow-loss events will occur at those lower elevations as well.  Even in the current climate, snowmaking for much of this new terrain is essential, and will become even more critical in the future.