Weather Window: The Storm King blows into Tahoe again
Special to the Sun
TAHOE/TRUCKEE, Calif. and#8212; The long hiatus between significant winter storms is officially over and Tahoe resorts are back in the game with top notch conditions. The latest surge of Pacific moisture came just in time for Presidentand#8217;s weekend, one of the busiest winter holidays, and just in time to recharge our dwindling snowpack.
Unlike 2009 when two storms blasted the region during the big holiday weekend causing traffic nightmares, most of this weekend is forecast to be fairly dry. The resorts should have hordes of happy skiers and riders enjoying high-quality powder.
Before this mid-February storm, rainfall totals in Northern California were at or below average for this time of year, a bit of a disappointment after the wet start. Those statistics will change in a hurry, however, as the atmosphere realigns itself enabling more Pacific storms to sweep into the west coast. Here in the mountains, snowfall accumulations ranging from 1-3 feet fell overnight as the cold front roared through. High wind gusts caused minor damage in western Nevada, but the most impressive speeds were over the Sierra crest where a non-thunderstorm wind gust reached 120 mph on Donner Peak Feb. 16 at 3:15 a.m.
Despite the long lull in moisture, there is plenty of good hydrological news. The Feb. 1, 2011 Nevada Water Supply Outlook Report stated regional and#8220;improvements in reservoir storage in many basins coupled with a projected above average runoff should lead to few water shortages this upcoming summer.and#8221; Current streamflow forecasts are optimistic, with above normal runoff expected.
Lake Tahoeand#8217;s water level has risen significantly this winter to 6,224.6 feet, about a foot and a half more than it was January 2010. Lake Tahoeand#8217;s reservoir storage is currently at 26 percent of capacity, which is about half the average for this time of year. The lake is forecast to rise an additional two feet by summer. The Truckee River Basin is looking good with Prosser, Boca, and Stampede reservoirs all running at or above average. In contrast, last year basin reservoir storage was only 76 percent of average.
January 2011 was one of the driest on record, with the Truckee River Basin receiving only 15 percent of normal precipitation, and the Lake Tahoe Basin not much better with only 22 percent. Despite the dearth of rain or snow during January, statistically the wettest month of the year, seasonal precipitation values are still about 150 percent for the region.
The prolonged period of high pressure eroded the snowpack considerably during what is typically the snowiest time of year. In some places the pack was cut in half, but testament to the huge snowfall numbers racked up in December, weand#8217;re still sitting pretty with about 130 percent of average in the upper elevations.
February is the third wettest month of the year, after January and December. On average it provides 16 percent of our annual precipitation and about 18 percent of snowfall. At the Central Sierra Snow Laboratory near Donner Pass, February produces about 8.5 inches of moisture with 73 inches of snow. Despite the late start, the recent atmospheric pattern change suggests that we should make that up in a hurry during the next 10 days.
and#8212;Tahoe weather historian Mark McLaughlin is a nationally published author and professional speaker. His award-winning books are available at local stores or at http://www.thestormking.com. You can reach him at firstname.lastname@example.org