After recent storms, Sierra snowpack is looking up
Another ‘atmospheric river’ forecast for weekend
Anyone looking up at the Sierra after the recent string of storms would conclude the snowpack is looking up.
They’d be right.
The most recent snow surveys show a significant jump in the region’s snowpack after a slow start to the winter storm season.
On Feb. 13, the Eastern Sierra snow load was about 83% of normal for that date, and 61% of normal for the April 1 average, when water managers estimate runoff for the season. The snowpack was holding about 14 inches of water equivalent, according to both in-person snow surveys and remote reports from Owens Valley Snow Pillows, according to the Los Angeles Department of Water and Power.
In a press release, LADWP noted the Feb. 4 storms dumped about one-quarter of an average year’s snowfall on the Eastern Sierra in less than a week. The powerful storms were “on trend” with the highest day totals from storms in January and March of last year.
INDEX QUOTE OF THE DAY
“It’s always too early to quit.”
– Norman Vincent Peale
A dry December and January had the snowpack lingering in drought territory. On Jan. 10, LADWP reported the snowpack had only hit 27% of normal for that date, which translated into a skimpy 13% of the April 1 average. The snow water equivalent at that time was just 3 inches. Those snow levels tracked the tiny snowfall during 2014-15, the driest year in LADWP’s record book.
Another illustration of how last month’s highcounty snowstorm have impacted the Sierra is the amount of snow measured at the base of the Mammoth Mountain ski area. In early January the base area had 65 inches of snow. As of Feb. 15, that number had climbed to about 197 inches. More than 10 feet of the white stuff has fallen on the ski hill over the past month.
Confusing winter weather
This winter has confounded most weather prognosticators. It has been an El Niño year, which typically means storms will deliver a higher dose of precipitation than in an average year. Southern California has seen significant rainfall and attendant flooding from a number of storms. (Los Angeles has received 14.5 inches of rain since Oct. 1, which is 90% of a year’s worth of precipitation.) However, with little snow or rain to start the winter in the Sierra, it seemed that long-term forecast for this region might not pan out. Which happens. Last year was a La Niña year, which was supposed to be a drier than average year. But it was a record setting year for rain and snow.
However, it seems the conditions are firming up for more storms to hit the Eastern Sierra. This weekend should see another “atmospheric river” event that could bring several feet of snow to the Sierra and possibly rain to the Owens Valley. A winter storm watch for most of Mono County has been posted for Sunday through Wednesday.
The six snow pillow reports from LADWP show a bit higher snowpack in the southern reaches of the Eastern Sierra.
The biggest snowpack in percentage terms is in Big Pine Creek, with about 16 inches of water equivalent, and 121% of average snowpack to date, which is about 89% of the April 1 average. Sawmill is at 91% of average to date and 89% of April 1, with 12 inches of water. Cottonwood Lakes, further south, is lagging a bit. It shows just 73% of average to date and 53% of April 1.
Gem Pass is at 57% of average to date and just 39% of the April 1 average. Mammoth Pass, with about 23 inches of water equivalent, is at 75% of average to date and 53 percent of a full year’s snowpack. Rock Creek is at 76% of average to date and 60% of the April 1 average.