The National Weather Service says Tuesday through Thursday, about a half-an-inch of rain is expected in the valley with an inch or so of rain in the foothills.
Mike Smith with the Weather Service in Sacramento says there's also a chance of thunderstorms and even a tornado.
"This is probably a pretty normal winter storm for a normal season, so it's not going to help a whole lot; it's just one system," says Smith. "The good news is, we do have more on the way. We're expecting more rain coming up this weekend and then possibly some more even going into next week."
He says the region is still a long way from normal when it comes to precipitation - but there's positive news in the forecast.
Smith says the storm is also likely to bring a foot or two of snow to the Sierra. He says gusty winds are possible, and there's a winter storm warning in effect from 3 p.m. today through Thursday morning.
As thousands of travelers hit the roads for the Thanksgiving holiday, a storm is dumping rain and snow in the Sierra Nevada and the Lake Tahoe region.
UPDATE: The National Weather Service has canceled a tornado warning for Sacramento County residents near Elk Grove and Wilton as of 6:30 p.m. Monday. Winds up to 25 miles an hour moved over Wilton.
UPDATE: The National Weather Service has issued a Flash Flood Watch through 9 p.m. Monday for the King Fire burn area in El Dorado and Placer counties.
The Pacific Storm system brought some slight improvement to drought conditions in California and Nevada last week.
The National Weather service has canceled a flash flood warning for Colusa, Lake and Yolo counties for Monday afternoon. A "flash flood watch" remains in effect until 8 p.m. for the burn areas.