The National Weather Service says a significant storm will bring between a quarter and a half-an-inch of rain to the valley and up to 2.5 inches of rain to the Sierra.
David Rowe with the weather service says there will be snow too.
"Probably about a foot to a foot and a half at the ski areas and maybe 2 to 3 inches down to about 4,500 feet," says Rowe.
Rowe says there are also flooding concerns in areas scarred by wildfire last summer -- for example the Rim Fire near Yosemite.
"When you get heavy rainfall intensity in a short amount of time, you tend to get mud and dust and debris left over from the fires last summer that'll accumulate and run downhill," he says.
Rowe says this will be a significant storm, but the region needs a series of these storms to start recovering from the drought. He says the forecast is dry again for the weekend and early next week.
Rowe urges valley commuters to use caution, especially Thursday morning, when the roads are likely to be slick, and says chains will likely be required in the Sierra.
The weather is about to change. Attached is the NOAA prediction for snow onI-80. Be prepared for winter driving. pic.twitter.com/kEvvfGXHAo— Caltrans District 3 (@D3PIO) January 28, 2014
A new study shows fire-fighting foam containing highly fluorinated chemicals is contaminating drinking water supplies around many of the nation's military bases, airports and industrial sites.
It has been a busy fire season across California. But there are fewer fires in the state’s 18 U.S. national forests so far this year, compared to 2015.
Update 8:00 p.m. Sunday: Crews are making "good progress" on the Cold Fire in Yolo County, now at 60% containment. In Monterey County, the Soberanes Fire remains at 45% containment with wind creating an additional challenge for firefighters.
The Soberanes Fire near Big Sur is burning in a rugged area that hasn't "seen fire in decades." The wildfire is 45 percent contained at 57,500 acres.
The number of acres burned by wildfires in the U.S. is about average for this time of year. But, in California, the 'new normal' includes larger and more frequent wildfires.