Just Like The Old Days — Big Snows In California’s Sierras

“I’ve been here since 1954 and I have to frankly say this is the harshest, toughest winter that I have ever had up here,” said Norm Sayler, 78, president of the Donner Summit Historical Society. Through Monday, the California statewide snow water equivalent was at 165% of normal. In a state that measures snow fall in feet this winter has truly been exceptional. So let me share some different perspectives about what a lot of snow means.

California Dreamin
It was just five months ago that Sierra snow lovers were getting worried. Worried about when winter would arrive. Just like the old Mamas and Papas song – California Dreamin – all the leaves were brown, the skies were grey, and the slopes were bare. November started dry and even by the middle of the month conditions were still dry. Drought had ravaged the state for years, and it seemed that Old Man Winter was late. But he finally awoke from his seasonal slumber and roared into the Sierras with vengeance. In the week before Thanksgiving Day storms dumped up to 10 feet of snow. Snow lovers rejoiced, and if there has been a problem, it’s that Old Man Winter never left. Across the region record to near-record snowfall has resulted in a snowpack that is reaching historic proportions, which is causing more than just inconveniences.

Snow devotee, Randall Osterhuber who also happens to be the director of the Central Sierra Snow Laboratory (and organizer of last fall’s excellent International Snow Science Workshop), told the Sacremento Bee, “It’s gone from deep to epic to dangerous.” Some of the dangers are obvious. Skiers and riders think of powder and hopefully too of avalanche and tree-well problems; home and business owners think of clogged driveways, parking lots, and stressed and collapsing roofs. Town and country road departments struggle with clearing snow and where to put the snow, but other dangers are not so obvious. Blocked flues and vents increase the danger for carbon monoxide poisonings. Loosened fittings on propane tanks caused by the tremendous load of snow might mean explosions. And there are problems with telephone and power lines. If not already buried, these lines are hanging at neck levels. Now this is a situation that few people have experience with.

Buried stop sign near Soda Springs, California. Photo by Rich Pedroncelli/Associated Press.

How Snowy?
Newspaper stories this morning are reporting that Osterhuber’s Central Sierra Snow Lab (CSSL) on California’s Donner Pass had 224 inches of snow blanketing the ground on Saturday. That’s about 18.5 feet or 569 centimeters or nearly 5.7 meters of crystalline water ice. Osterhuber had to add a 6-foot extension to his stake after his 15-foot stake was buried. With an average maximum depth of 3.4 meters (~138 inches), the CSSL, this is a spot well known for deep snows and tragedy.

The Donner Party (It Wasn’t Really A Party)
The CSSL, which is located at about 6,900 feet (~2100 meters) on a pass named for the infamous Donner Party, and by party, I don’t mean a social gathering with a goal of having a good time. Rather the Donner Party was a group of 80-some California-bound pioneers who became snowbound on the east side of the pass during the winter of 1846–47. By late October the group was ready to cross the mountains, but winter arrived early and halted the party. By Christmas more than 12 feet of snow covered the ground. Trapped for nearly four months some of the people resorted to cannibalism to survive. Only 48 survived.

Fast forward 164 years to this winter and while no one has been known to be have been trapped and resorted to cannibalism. (Though I am sure many were stuck at home and ran out of beer and chips.) To avert any potential calamities, the Union Pacific Railroad did close their tracks over the summit for five days. It has been years since such a prolonged closure. Yesterday, the rail line was reopened after historic steam-driven rotary plows and about 100 workers cleared 50 miles of snowbound track. It had been 15 years since the rotaries were last used. Just these actions taken along the rail line, have to remind old and long-time locals (or historians) of the big winter in 1951-52.

The Big One — 1951-52
Since manned observations started at CSSL in 1946, the winter of 1951-52 saw the deepest snow pack in recent history when 20.57 feet of snow covered the ground on March 19, 1952. Maximum snow depths are usually reached in April, and currently with a depth at 18.5 feet it looks like a modern record might still be in reach.

You can download a great article with lots of pictures (click here) about the winter of 1951-52 from the Donner Summit Historical Society.

Also, check out Mark McLaughlin’s website The Storm King for a more great stories and data.

I use “modern” to differentiate between eras in snow observations. Post 1946 trained weather observers have recorded weather observations. Prior to 1946 the Southern Pacific Railroad kept records that go way back to 1879, and the quality of the data is…; well, let’s just say that some of the earliest observations raise some eyebrows. Before the end of the 19th century, two winters were reported to have had maximum snow depths of 30 and 31 feet.  No other winters in more than 100 years have come close.

2010-2011:  A Tremendous Load
A “tremendous load” is a good phrase to describe this spring’s snowy situation. The amount of water contained in this snow cover is staggering. If you were to melt the 200+ inches of snow on the ground there would be a puddle, actually more like a shallow fresh-water sea 5 to 6 feet deep. In the business we call it the snow water equivalent, abbreviated SWE. We Yanks report SWE in inches. In several Sierra locales the SWE has already reached 70 inches. And there is still another month of snow season to go. At Leavitt Lake near Sonora Pass, the SWE just topped 80 inches. When you figure that 1 cubic foot of water contains 7.48 gallons, which tips the scales at about 62.4 pounds, you quickly realize the enormous weight and volume of water equivalent that covers the land, and your roof too.

[Click on images to see full-sized.]

Depending where you live (including your elevation) in the United States, and the type of structure, a typical roof is built to support a snow load of 12 to 80 pounds per square foot. A very simple rule of thumb to estimate snow loads is to figure that a cubic foot of snow weighs between 10 and 20 pounds (however, in snow country by spring, the season’s accumulation can weigh much more), and most roofs should support up to about 4 feet of snow. If you have a cabin high in the Sierras and haven’t yet shoveled your roof, now would be a good time to start shoveling. (If you’re going to shovel, think avalanche. Roof avalanches have killed people.) The snow load of the entire snow pack can be well north of 300 pounds per square foot. While all this snow is not welcomed on roofs, its water will be well welcomed later this spring and summer as it fills the state’s parched reservoirs.

Snowy Mountains
Named by early Spanish explorers the Sierra Nevada mountains are aptly named as it means snowy mountains in Spanish. This winter is again demonstrating their heritage. This afternoon California state water officials are expected to release results from the latest snow survey. Word in Sacramento has it that Governor Brown will declare the state’s drought officially over. Since 2009 the state has been a “state of emergency” because of the lingering drought.

According to the California Department of Water Resources the mountain snowpack provides one-third of the water for the state’s households, industries and farms. The water goes to more than 25 million Californians and irrigates nearly 1 million acres of farmland. The last time the state’s water projects were able to deliver 100% of the allocated water was back in 2006. Then the drought struck; water deliveries over the next four years dropped to as little as 35%. This winter’s snows looks to break the drought but water delivers are expected only to be about 70%, a huge improvement but still far below the requests for water.

While farmers and ranchers are rejoicing with the prospect of seeing the state’s reservoirs fill, property owners and snow workers, from part-time shovelers to plow drivers to even ski patrollers will probably be glad to see this winter end. But even the most crusty, old-time ski patroller (or avalanche professional) who complains about this too-long winter, will always remember this winter with special fondness. In a muted voice, or after a few beers, their eyes will sparkle as he or she admits to the winter being special. The bountiful snows mean good news for the skiers and riders as ski areas are extending their seasons. Squaw Valley will stay open through Memorial Day and Mammoth is talking about staying open to the Fourth of July. Be sure to check your local ski area for their plans.

With April just a couple of days away, the snow season will be winding down. May snow storms can still hit hard the Sierras, but usually by May the weather turns sunny and dry, conditions that last through September. For people that keep track of records, it will be nice to see a bit more snow, at least enough to break the record. But, to me it really doesn’t matter whether the record falls, or not. The spring ski season will be spectacular and shall last well into the summer. I hope you can get out to enjoy the Sierras. I am planning for a visit.

Thanks for reading.
Dale Atkins

This entry was posted in News, Weather. Bookmark the permalink.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )


Connecting to %s