Sierra snowpack in spring
While this season doesn’t nearly trump the amount of snow received during the 2016-2017 season, when many resorts received almost 700 inches of snow at summit elevations, the 2018-2019 ski season is stacking up with lots of precipitation. Many resorts are reporting well over 200 inches just for base depth, prompting ski areas around the basin to extend their seasons.
Mammoth has received the most snow thus far, with summit season totals reaching 635 inches as of early March. Squaw Valley comes in second at 618 inches—and both resorts plan on staying open until July. Vail resorts also announced that Kirkwood will stay open until April 14, Heavenly until April 28 and Northstar until April 21. Included in these extended dates are bonus three-day weekends, May 3 to 5 at Heavenly, and April 19 to 21 at Kirkwood.
February 2019 also marked Squaw’s snowiest month on record, breaking the 2016-17 season record, with 300 inches of snowfall compared to the previous record of 282 inches. According to the California Data Exchange Center, snowpacks around the basin are already 160 percent of average, and the lake is within a foot of its maximum capacity, sitting at 6,228 feet and pushing the legal limit of 6,229.1 feet. The legal limit on the amount of water that can be stored in Lake Tahoe is written into federal law and spelled out in the 1935 Truckee River Agreement. That agreement was itself years in the making. According to Tahoe weather historian Mark McLaughlin, it was hammered out after several epic winters in the early 20th century left the lake level high enough to erode land around its shores, causing concerns for property owners—while, simultaneously, premature releases of water from the lake left farmers downstream in Nevada with a water shortage later in the season.
Lake Tahoe’s natural rim sits at 6,223 feet. Water can be released from the lake when its level sits at 6,228 feet—and forecasts predict more precipitation.
Snow forecaster Bryan Allegretto said the end of March and early April have the potential to bring more precipitation.
“There is a fairly strong jet stream across the Pacific by the 20th trying to push storms into the West Coast,” Allegretto said.
At this point, it is too hard to tell the significance of these storms, but models show increased chances of precipitation, according to Allegretto.
This means flooding could potentially hit the Truckee River this spring. Already, flood gates were opened in February during the record breaking snowfall. Currently, 11 of 17 gates are open where the mouth of the Truckee River is dammed in Tahoe City. United States Geological Survey models show that anywhere from two to three feet of water could enter the lake during spring and summer snowmelt. And the Truckee River is already flowing high, at 1660-cubic-feet per second (cfs) as of March 10.
Monitoring the lake’s level will become increasingly important as the busy summer tourism season begins at Lake Tahoe. High lake levels will limit beach space and make already slim shoreline areas inaccessible. High lake levels can also erode lake shores, which can affect water levels and clarity—especially when additional sediment flows into the lake during snowmelt.