RENO, Nev. — A fierce winter storm packing winds in excess of 100 mph (160 kph) and predicted to bring as much as 8 feet (2.4 meters) of snow to the Sierra Nevada barreled into the West Coast on Monday, toppling trucks, triggering power outages and temporarily closing the major highway near Reno.
Up to a foot (30 centimeters) of snow already had fallen in parts of Oregon, forcing school closures and delays, and a blizzard warning was in effect in parts of Montana.
Winds gusting to 110 mph (177 kph) were recorded at the summit of the Squaw Valley ski resort near Lake Tahoe, and up to 84 mph (135 kph) in the valleys along the Sierra’s eastern front where Interstate 580 was closed off and on between Reno and Carson City.
Two trucks overturned on I-580 and another on nearby U.S. 395 in the Washoe Valley, where one non-life threatening injury was reported.
At one point as many as 6,000 NV Energy customers were without power in the Reno-Sparks area, but power had been restored to about half by Monday afternoon.
Schools throughout Oregon delayed start times or closed altogether. About a foot of snow (30 centimeters) was reported in areas including Eugene and Bend, producing slick roads and causing canceled flights at Portland’s airport. The city of Eugene declared an ice/snow emergency requiring drivers to remove vehicles from snow emergency routes.
Devon Ashbridge, a spokesperson for Lane County, said that although snow plow crews had been working since Sunday, roadways were still relatively treacherous with hundreds of downed trees and power lines across county roads.
A swath of western Montana from Missoula through the Bitterroot Valley was under a blizzard warning through Monday evening, with an inch or two (2 ½ to 5 centimeters) of snow expected to fall each hour. The National Weather Service has issued winter storm warnings and advisories for most of the rest of Montana through Tuesday morning.
In the Sierra along the California-Nevada line, a winter storm warning remained in effect for the Lake Tahoe area until 4 a.m. Thursday. The forecast calls for winds gusting in excess of 140 mph (225 kph) over ridgetops.
“Periods of white-out conditions are likely,” the National Weather Service in Reno said. “Very strong winds could cause extensive tree damage.”
No new snow had fallen in the Sierra by Monday afternoon, but 2 to 4 feet (61 to 122 centimeters) is expected over the three days, with 4 to 8 feet (1.2 to 2.4 meters) possible above elevations of 7,000 feet (2,134 meters), including where U.S. Interstate 80 crosses the top of the Sierra at Donner Pass southwest of Truckee, California.
The latest storm will be a “marathon rather than a sprint,” the service said, in terms of accumulation with several wet feet of new snow expected over top of a drier layer of powdery snow through early Thursday.
“Travel will be tough and possibly impossible at times through the Sierra with no clear break in snowfall once this begins,” the service said.
A winter weather advisory goes into effect Monday evening along the California-Nevada line from 100 miles (160 kilometers) south of Tahoe near Mammoth Lakes, California, to 100 miles (160 kilometers) north of Reno near Gerlach.
The service said the new snow load coupled with expected winds may result in unstable slope conditions in the Sierra with the potential for avalanches and “rooflanches.”
“Do not linger under eaves of buildings that have a large quantity of snow on its roof,” the service warned.