If the lake level drops below 3,490 feet - termed the minimum power pool - the turbines that generate electricity have to be shut down. When the water level reaches critically low thresholds, air is sucked down like a whirlpool into the penstocks, forming explosive bubbles which can cause massive failure inside the dam.
SWE is the most important metric for all of our water resources. It's the metric that we deal with the most and the one that the entirety of the snow research and operations community is working to get right. So, seeing an increase in SWE like that, even if it's from mid-winter rain, is a great thing because that means we have more water stored in the snowpack moving forward.
"A dry January, which is historically the wettest month of the year in California, has now eroded the gains made at the start of the year and forecasts currently show no major precipitation in the next two weeks," California Department of Weather Resources spokesperson Jason Ince wrote in a Jan. 30 news release. The first month of the year certainly left the area warmer and drier than usual, weather officials confirmed.
Avalanches kill about 100 people in Europe each year, with vast masses of ice, snow and rock regularly crashing down on hikers and skiers who have been caught unawares. The structure of the snow, angle of the slope and variation of the weather can dictate whether a gentle disturbance like a gust of wind or the glide of a snowboard can trigger a deadly shift in the mountain.
If you are reading this on the East Coast, congratulations on the warmer weather you're finally getting this week. It was cold and snowy for a while there. Here in the West, we wish we'd been in your shoes. Spare a thought for the tens of millions of us who live on the other side of the continent, where a catastrophe is unfolding.
To get back to average snowpack, we essentially need to have the most snow that we've ever had for the last 30 years between now and mid-April. It would be extremely difficult for Colorado to get back to a normal/average snowpack. As an example, when looking at the Independence Pass SNOTEL site in central Colorado outside of Aspen, we typically have 13 inches of snow-water-equivalent at the end of February. This year, we only have 6.7 inches of SWE.
Sun night (02/15) through Tue night (02/17) is the core punch, and many Sierra mountains can stack 20″-50″ in that window as snow levels crash. Expect a lighter start Sunday night, then snowfall rates ramp up hard Monday night into Tuesday with widespread coverage across Tahoe, the central Sierra, and down into Mammoth. Snow levels begin around 5,000 to 5,500 feet early, then fall into the 1,500 to 2,500-foot range by Tuesday and Tuesday night, which helps keep even lower terrain in play for all-snow.
Vail Mountain has recorded its lowest snowpack in 47 years, with just 67 inches of snow so far this season. It has been a tough season so far for many resorts located in the Rockies and out West. "We experienced one of the worst early-season snowfalls in the Western U.S. in over 30 years," Rob Katz, Chief Executive Officer, said in a press release. This has limited Vail Mountain and other resorts from opening new terrain and has decreased skier visits.
Confidence is highest through Saturday because the individual models agree well on the timing of the Thursday storm and the following break. Southern California's mountains pick up a quick shot of snow on Thursday with strong winds, then dry out into the weekend. Beyond the weekend, the signal stays active, but model spread grows fast on storm timing, snow levels, and wind impacts, so expect meaningful swings from run to run.
Many of us are riding the high of the recent major snowstorm wondering when the next big powder day will swing through. Unfortunately for most of North America, it looks like the snowy weather won't be returning anytime soon, or at least not for the next week. Meteorologist Chris Tomer 's Mountain Weather Update paints a rather sad picture for snowfall totals in North America between January 29th and February 5th.
