The latest in the long onslaught of storms that began in December has pushed California’s snowpack to its highest level on record. This week’s storm dumped another one to two feet in the Sierra Nevada helping this season eclipse 1982-83, the previous record-holder.
By far, the central and southern Sierra have seen the most unusual amounts of snow, with their snow water content 233 percent and 298 percent of normal, respectively. Comparatively less snow has fallen in the northern Sierra, whose snow water content is 190 percent of normal and still trails 1982-83.
The enormous snowpack has accumulated mostly because of 17 atmospheric rivers — or potent jets of subtropical moisture — which have bombarded the state since December, according to the Center for Western Weather and Water Extremes in La Jolla, Calif. Several non-atmospheric-river storms have also hit the state.
Snow totals at ski resorts in the Sierra Nevada have reached unheard of heights in some instances, even burying chair lifts.
We have #AtmosphericRivers to thank for all this recent rain! 🌧️ The team from @CW3E_Scripps says we are at 31 atmospheric river events so far this water year (11 weak, 13 moderate, 6 strong, 1 extreme). Here is the map of where and when they all hit. ⬇️ pic.twitter.com/tbh3egHnb8
— Scripps Institution of Oceanography (@Scripps_Ocean) March 29, 2023
Mammoth Mountain announced this week that it had clinched its snowiest season on record with 702 inches at its Main Lodge. Since it started tracking snowfall in 1969-70, the prior top mark was 668.5 inches. At the mountain’s summit, Mammoth measured 879 inches.
Gridded snowfall analysis from the National Weather Service suggests that some totals are past 900 inches in the snowiest spots of the Sierra.
At the Central Sierra Snow Lab not far from Lake Tahoe, the seasonal total surpassed 700 inches after this last storm. Its seasonal total is now up to 713.8 inches, second most on record.
Other substantial totals in the Sierra include:
·755 inches — Sugar Bowl.
·723 inches — Boreal Mountain.
·722 inches — Dodge Ridge.
·696 inches — China Peak.
·695 inches — Kirkwood.
·692 inches — Palisades Tahoe.
Snowpack typically peaks around this time of year, but resorts in the Sierra can still expect another 3 to 6 feet of snow on average through the end of the season in May or June, which means these totals may well climb more and additional records set.
The vast amount of snow, combined with heavy rain at lower elevations, has made a massive dent in the state’s drought. The federal government’s latest drought monitor, released Thursday, showed drought covered just 28 percent of California compared with nearly 100 percent in early October.
Computer model projections show yet another storm could hit the state early next week, with more rain at lower elevations and heavy mountain snows, especially in the northern and central parts of the state.
After the middle of next week, a drier pattern may well develop over the West Coast. The Weather Service’s Climate Prediction Center leans toward below-average precipitation for California in its 6- to 10-day outlook.
“That would be welcome news as I think we’re all ready for a break,” wrote the meteorologist who prepared the Weather Service’s Bay Area office Thursday morning forecast discussion.
But once the precipitation cuts off, concern will turn to the prospect of warmer temperatures that could rapidly melt the snowpack as the spring wears on, causing flooding.
“It is important to understand that we are in uncharted territory,” Jeffrey Mount, a senior fellow at the Public Policy Institute of California’s Water Policy Center, told The Post earlier this month. “The amount of water tied up in snow in the watershed is about twice the average amount of runoff in an entire year.”
