As if enough snow hasn’t already fallen in the Sierra Nevada this winter, Mother Nature is sending more over the next few days. Compared to this time last year, about 12 percent less of the region is covered by snow. However, the average depth of the snow is far greater right now than a year ago – 40.4 inches compared to 22.9 inches – and the the maximum depth is at around 200 inches. This is because the region has had many more storms than last winter, and some of them have produced massive amounts of snow for up to five-day stretches.
Getting Buried Again
The center of the current storm, which FreightWaves first mentioned yesterday, moved closer to the West Coast last night, sending a constant stream of Pacific Ocean moisture into the region. Moderate snow will fall across the Sierra today (March 5), becoming heavy tonight and Wednesday. Then the storm will fade, but light to moderate snow will continue on Thursday and Friday, along with snow levels dropping into the foothills.
In keeping with most of the storms this winter, some of the heaviest snow will likely fall in western Plumas County and Lassen Volcanic National Park, with accumulations of 12 to 36 inches. However, there could be isolated spots of four to five feet accumulations. The west slopes in the northern Sierra may also see up to four feet, possibly leading to delays or closures on I-80 over Donner Pass, as well as US-50 over Echo Summit.
The highest elevations of Yosemite, Kings Canyon and Sequoia National Parks are poised to get slammed with up to three feet of snow. On the eastern slopes, including Aspendell and Whitney Portal, storm totals of 12 to 24 inches will be common, but larger accumulations are possible above 9,500 feet.
Some parts of western Nevada will also get their share of snow from this storm. Total accumulations of 12 to 24 inches will cover elevations above 7,000 feet in the greater Lake Tahoe Area, including the cities of Incline Village, South Lake Tahoe, Stateline and Truckee. There’s a good chance of higher totals west of CA-89. Look for four to eight inches below 7,000 feet, with two to five inches at lake level.
Strong wind gusts of 50 to 80 mph will lead to blowing snow and whiteout conditions across many parts of the region.
Heavy snow is also forecast for the Cascades of northern California. From around Mount Shasta northward into Siskiyou County, an additional 10 to 20 inches could pile up through Wednesday evening in the higher terrain. The snow level will drop below 4,000 feet at times this evening, with an inch or two possible as low as 3,500 feet. Drivers should be prepared for slick conditions over Black Butte Summit on I-5 where light accumulations are possible.
Winter Storm Warnings have been issued by the National Weather Service (NWS) for most of the Sierra Nevada Range, with Winter Weather Advisories along the Nevada state line.
Lots of snow will spread into southern Oregon, too. Totals of eight to 14 inches are expected across the Cascades and the Klamath Basin, impacting travel over mountain passes on OR-140, OR-230, the Crater Lake area, and US-97 from Modoc Point to Chemult.
Here Comes the Rain Again
This storm will be a big rainmaker for the lower slopes and foothills of the Sierra, as well as the Central Valley from Redding through the Sacramento metro area. The lower slopes and foothills could get drenched with three to six inches of rain over the next few days, while the Central Valley is looking at one to three inches. Soils are already saturated from recent rains; in addition to streams, creeks and rivers running high, this next round of wet weather may increase the risk for flooding again.
This means there’s also a potential for mudslides, rock slides and debris flows blocking roads. Occasional thunderstorms will produce intense downpours at times, especially on Wednesday. The Los Angeles metro area will also be under the gun for flooding, from the coast to the adjacent mountains.
Impact on Freight
The Sierra Nevada Range is flanked to the left by the Stockton, California market, and to the right by the Reno, Nevada market. A large majority of volume into Reno comes from Sacramento, which is in the Stockton market. As of this morning (March 5), FreightWaves data shows a sharp increase in the percentage of loads being rejected into the Reno market (ITRI.RNO). The rise started just before the arrival of the storm today. It’s possible that carriers are just sick of all the snow and rain, and don’t want to send many drivers through the Sierra due to the high odds for delays and risky road conditions.
Look for more weather updates throughout the week on the FreightWaves website.