Storms cause travel problems in the Sierra, but bring needed rain and snow

The first of two major winter storms arrived Thursday, bringing rain to the Sacramento Valley and snow to the mountains, causing challenges for commuters but providing optimism for scientists watching California's snowpack. 

Interstate 80 was closed for a time Thursday evening near the Nevada border, though the westbound lanes reopened at 4:30 p.m., according to Caltrans. You can find updated road conditions on the Caltrans QuickMap.

"Drive safe, drive with caution on those slick roads and give yourself extra time to reach your destination,” said Katrina Hand, a meteorologist with the National Weather Service. 

The Sacramento region could get up to an inch and a half of rain Friday and about half an inch over the weekend. The Lake Tahoe area could get up to two feet of snow. 

"This is a colder system,” said Hand. “It's coming up from western Canada, Gulf of Alaska area and we are seeing heavy mountain snow associated with these winter storms and up in the mountains we are expecting several feet of snow up at the highest peaks."

While this winter storm doesn’t yet compare to last year’s record-breaking December snowfall, experts say it’s promising for California’s snowpack. 

"This is a really big snowstorm which will set us up really well for the winter, assuming we keep getting snow and we don't get any long droughts like we did last year," said Andrew Schwartz, the lead scientist at Berkeley’s Central Sierra Snow Lab. "Fingers crossed we don't go into the wild weather whiplash situation that we did last year where we were going from extreme wet to extreme dry over and over again. Unfortunately, those types of seasons are becoming more common under climate change."

Schwartz said the lab measured six inches of snow Thursday morning and were expecting another 20 to 30 inches during the day. A winter storm warning is in effect until early Friday morning. A dense fog advisory was also issued for portions of the Sacramento and San Joaquin valleys from 1 a.m. through 9 a.m. Friday. 

While some clear skies returned Thursday afternoon, rain and snow are predicted to return Saturday. Hand with the weather service said that could continue to impact travel throughout the region through the weekend.

"We do have these two storms coming through and then lingering showers on Monday,” said Hand. “Beyond that, it is a little uncertain at this time. But it is hopeful as this rain is certainly beneficial for our area."