A powerful storm dumped record levels of rain in Sacramento and at least a half an inch of snow in the mountains Saturday - on the last day of summer.
Northern California got pelted with as much as an inch of rain by mid-afternoon, overflowing leaf-clogged storm drains, causing street flooding in residential areas, and forcing foothill residents indoors under the threat of lightning storms. Unseasonably cold temperatures turned that rain to snow in the mountains, causing Caltrans to impose chain controls on Interstate 80 westbound over Donner Summit late in the day.
Downtown Sacramento got .41 of an inch by 4 p.m., far surpassing the previous record, .15 of an inch, set in 1916, according to the National Weather Service. More than an inch fell in Redding, setting a record for the day. Stockton and Modesto also recorded record amounts.
The National Weather Service tweeted an afternoon warning to mountain residents: When thunder roars, go indoors! The storm caused a mudslide on Highway 193 near Placerville, led to several roadway spin-outs, and slowed traffic on Interstate 80, the California Highway Patrol reported.
Weather service forecaster Brooke Bingaman said the storm should tail off this afternoon. "Once we get past 5 p.m., there is still a chance of showers, but it should be diminishing."
Saturday night's low temperature in downtown Sacramento will be 54 degrees, with diminishing chances of rain.
Sunday will usher in fall with sun and a breeze. Expect a high of 77, or 10 degrees below average. The low should reach about 57.
The summer was "very dry," and with reservoir systems below normal, "it's a good thing we are getting rain earlier that is coming in to refill those reservoirs," Bingaman said.
Summer also brought fewer 100-degree days than normal, she said. The Sacramento region averages 22 per year, but summer 2013 had 17.
Here's the seven-day forecast:
Saturday: Rain showers likely in the morning ... then rain showers likely and a slight chance of thunderstorms in the afternoon. Cooler. Highs 67 to 73. South winds 10 to 15 mph with gusts to around 25 mph.
Saturday night: Mostly cloudy with a chance of rain showers and a slight chance of thunderstorms in the evening...then mostly clear after midnight. Lows around 52. South winds up to 15 mph.
Sunday: Mostly sunny. Highs 72 to 80. Northwest winds up to 15 mph.
Sunday Night: Mostly clear. Lows 52 to 58. West winds up to 10 mph.
Monday: Mostly sunny. Warmer. Highs 80 to 88. Northwest winds up to 10 mph.
Monday Night: Mostly clear. Lows 53 to 59.
Tuesday: Mostly sunny. Highs 77 to 83.
Tuesday Night Through Thursday Night: Mostly clear. Lows 50 to 57. Highs 73 to 83.
Friday: Mostly sunny. Highs 80 to 86.
Call The Bee's Tony Bizjak, (916) 321-1059.