In the Jan. 28 weekend edition of the Tahoe Daily Tribune, a letter to the editor was published regarding the discrepancy of snowfall totals reported during the last pair of storms. This column attempts to explain why snowfall totals can vary considerably within our region.

Lake Tahoe sits on the east side of the Sierra Nevada and on the west side of the Carson Range. The Sierra Nevada stretches from the northwest to the southeast, from Quincy to Lake Isabella. The Carson Range stretches north to south from west of Reno to west of Markleeville. The Sierra casts a pronounced “rain shadow” across those areas that are downwind or east of the mountain chain. Since most of our precipitation comes from the west during fall, winter and spring, the Lake Tahoe area receives about half as much precipitation as the western slopes.

According to past records, the average annual snowfall at the South Lake Tahoe airport is approximately 213 inches. (Unfortunately, the airport no longer measures snowfall). The Coast Guard office east of Tahoe City averages 189 inches annually. The amount of snow is actually greater in Tahoe City than at the Coast Guard because of their locations relative to the Sierra Nevada.

By contrast, Glenbrook on the Nevada side of the lake only averages 90.3 inches of snow annually, a rather large difference. Echo Summit, located at the top of Highway 50 at 7,300 feet in the Sierra averages 412.5 inches of snow annually. Daggett Pass located at 7,300 feet on the top of Kingsbury Grade in the Carson Range only averages about 193 inches of snow annually.

These examples show that the farther east fromthe Sierra you go, the less precipitation you receive. Depending on where you live in town, parts of South Lake Tahoe actually average more snow than those who live at higher elevations on Kingsbury Grade. Residents of Meyers and Christmas Valley can easily attest to this fact. This is due again to the rain shadow of the Sierra Nevada.

As the Pacific storms ascend the west slopes of the Sierra, they deposit most of the moisture there along with areas immediately to the lee on the eastern slopes, such as Meyers and Tahoe’s west shore. It is quite common for areas along the Sierra’s east slope in Meyers to accumulate 2 feet of snow from a storm while Zephyr Cove on Tahoe’s east shore accumulates only 10 inches. In South Lake Tahoe, the closer you are to the “Y” the more precipitation you will receive. The closer you are to Stateline the less precipitation you will receive. Most residents who have lived in the area for some time can verify this to be true.

As a National Weather Service spotter, I gather snowfall data from a location in the geographical center of South Lake Tahoe approximately half way between the “Y” and the state line. This gives a good average for the town.

Unfortunately I do not know where the snowfall amounts listed in the paper are recorded; however, a few factors could affect those numbers. Location is probably at the top of the list. For example, snowfall amounts should be measured in an open area, not under a dense canopy of trees where the amounts would be considerably less.

Hopefully this column will serve to answer some of the questions people have as to how different locations within a small radius can receive large variations in precipitation totals.

-Simon Smith is a National Weather Service spotter in South Lake Tahoe.

Simon Smith

P.O. Box 13565

South Lake Tahoe, CA 96151

(530) 544-0659