The “Bomb Cyclone” crushed the West last week and became a skiers dream, especially in the Sierra and Four Corners region of Arizona, Utah, New Mexico and Colorado. That, combined with cold air, became the first major storm to hit the Sierra for the season. Two to three feet fell in many areas, even at lower elevations. That snow brought California from nada to locals hitting the slopes on Thanksgiving, just waiting for more terrain to open up. It's amazing how fast conditions can change in a matter of just a week. Squaw Valley Mountain Manager Jimmy King described the upper mountain is "a whole new world." Just what is a “Bomb Cyclone,” as it certainly sounds pretty euphoric as a skier. Officially, it's a rapid destabilization of the atmosphere (rapid drop in barometric pressure) that leads to rapid intensification, which often leads to intense weather events. The term is also coined as a “Meteorological Bomb”. As a snowboarder, I think I would get pretty excited to wake up to a forecast that a Meteorological Bomb was about to hit.
According to Zach Tolby from the National Weather Service in Reno, “it's not unusual to see significant storms hit the Sierra in November. What is unusual is the dramatic change from virtually no moisture to 3 significant events all within a nine day period.” Zach is also an avid skier, so he welcomes the change. He also said “It was pretty impressive to see how fast the atmosphere destabilized on the first major storm to hit California last week.”
That system dropped south into the Four Corners and parked itself on top of Arizona for two days, bringing record dry-density powder to the Arizona Snowbowl, with openings last Friday and Saturday both reporting an excess of 20 inches overnight (58 inch storm total). That sent every local up the tiny access road, snarling traffic and eventually overcrowding the resort and closing the road. “One car out, one car up.” I doubt anyone left early!
Meanwhile, strong SW winds pushed copious amounts of moisture north into the Wasatch Range, bringing storm totals in the 50-65 inch range for many areas in Utah. On the tail end of that storm, the Tetons were awakened to 20 inches of new snow that fell overnight on Saturday. Avalanche activity was very active in the Wasatch with multiple slides being reported during mitigation at the ski areas (1 patroller at Snowbird went for a ride).
And yet another storm just crushed the Sierra with an additional two to three feet of “Cement” on Monday morning, which is exactly what they needed for base building. This storm was an atmospheric river that brought some warmer air and much less snow at lower elevations.
Below: Sierra At Tahoe Ski Area Monday morning. Deep cement is exactly what Tahoe needed.
Here are some impressive snow totals from the West over the past 7 days:
Kirkwood: 85 inches
Squaw Valley: 75 inches
Mammoth: 74 inches
Northstar: 73 inches
Alta: 68 inches
Arizona Snowbowl: 54 inches (Dessert Pow)
Snowbasin: 51 inches
Park City: 48 inches
Wolf Creek: 30 inches
Taos: 26 inches
JHMR/Targhee: 20-25 inches
Below: Water percentages as of November 26th. Only 18% of normal around the Tahoe Basin and 0% to the north. Image: NRCS- November 26
Below: Current percent of normal in the Sierra range as of December 3rd. Over 200% of normal noted for the Tahoe Basin. Significant change from the map above in just a 7 day period where the Sierra range went from 18% to 211% of normal.
Below: General map of the West showing above average water content currently in many areas of the west. The 150% range is in the Wasatch while the 300% and greater ranges are in southern Utah and northern Arizona. The Tetons are sitting around 90% while the Pacific Northwest is significantly below average.
Another significant storm is on tap for the Sierra this weekend. Cold air from Alaska will merge with warmer Paciifc moisture this weekend, bringing two to three feet of additional snow to most of the Sierra range. This system will be colder than the last one. (Snow levels around 5K perhaps lowering by Sunday). This will bring a healthy dose of medium density to pow to most resorts including Mammoth. The sum totals after this weekend will exceed 100 inches for the 9 day period for most resorts in the Sierra.
Below: Total additional snowfall for the Sierra through Sunday. 30-40 inches noted at the Sierra Crest however amounts may stay in the two to three foot range generally at most ski areas. Image: WeatherBell
Elsewhere in the West, I see moderate snow to develop in the Tetons, central Idaho and even the Cascades this weekend. This will reach the Wasatch by late Saturday-Monday. While not a major event, it's likely that some spots in Wyoming and Utah end up in the 8-16 inch range. I favor the Tetons slightly. In Colorado snow will be falling Sunday PM to Tuesday with perhaps 5-10 inches for resorts along I-70 favoring the central mountains towards Aspen or Crested Butte. The models are not in sync so at this point, confidence is low on who sees the most snow.
Beyond the 7 day period it looks like high pressure will return to the West as the storm departs Colorado next Tuesday.
Below: High pressure settles into the West on December 10th as the system pushes east of Colorado. Image: WeatherBell
Enjoy the powder everyone! Let's hope another Meteorological Bomb hits us again this winter! I could take that everyday of the week!
-Powderchaser Steve
About The Author
stash member powderchaser Steve
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