SACRAMENTO, Calif. — Update 7:45 pm

Heavy rainfall courtesy of thunderstorms has produced localized flooding in El Dorado, Amador and Calaveras Counties. For this reason, the National Weather Service has issued a Flood Advisory until 10:45pm. 

FLOOD ADVISORY
ABC 10

Rain showers will begin to wane in the overnight as a cold front crosses the area. More isolated thunderstorms are possible Sunday for the valley and foothills as a low-pressure system moves through the area. 

Snow showers will continue to be heavy overnight with white-out conditions expected for the Sierra above 6,000 ft in elevation.  A Winter Storm Warning remains in effect til 12pm Sunday for the Lake Tahoe area. 

Expect improving conditions during the day Sunday.  

WINTER STORM WARNING
ABC 10

Update 4:50 p.m.

Thunderstorms are moving into Grass Valley along Highway 50 and many Foothill locations along Interstate 80. 

This line of strong thunderstorms is moving east at 35 mph. These storms are capable of producing torrential rainfall along with pea-sized hail. 

 Be advised you may run into localized flooding in some low-lying areas.  Remember: Do not drive your vehicle through flooded roadways. 

Update 4:00 p.m.

A man and a woman were taken to the hospital after being struck by a fallen tree on a San Francisco sidewalk. 

The wind likely knocked down the tree as a winter storm brought strong wind along with heavy rain and snow across Northern California on Saturday. Flooding in San Francisco's subway tunnel halted train service, a rock slide partially shut Highway 1 in scenic Big Sur and winds gusting up to 40 mph contributed to dozens of canceled or delayed flights at San Francisco International Airport. 

Meanwhile, a flash flood warning was issued for areas burned by a large wildfire in wine country last month because heavy rain could trigger a flow of mud and debris.  

Update 2:24 p.m.

The National Weather Service in Sacramento has issued a flood advisory for a part of Shasta County.

An areal flood advisory was issued for south central Shasta County and north central Tehama County. NWS Sacramento said between 1 and 2 inches of rain has already been recorded.

Original:

It's been under 10 days and already three winter storms have rolled through Northern California. So what gives?

First off, it's safe to say Mother Nature has flipped the switch on dry weather. Starting off November, Sacramento was in over a 1.50 inch rain deficit. Now, we're closing that gap. As of Dec. 6, Sacramento has accumulated 2.99 inches of rain. The average for this time of year is at 3.58 inches. A deficit of -.58 inches.

We've all heard of the Pineapple Express -- warmer air and moisture out of the Hawaii region that moves into California. That moisture is responsible for ramping up rain and snow fall. When a low pressure system taps into that Pineapple Express, also known as an atmospheric river, it can funnel in moisture for days.

Now before all this moisture arrived, Friday was a beautiful, sunny, and warm day. Dec. 6 saw a daily record temperature tied at 68 degrees. This temperature was also recorded in 2014 and 1989.

As much as .50 to .75 of an inch of rain is possible through Sunday morning in the Valley. 

The California International Marathon will take place Sunday, and runners want to know: how will this affect my race?

Early morning rain will fall from about 2 a.m. to 4:30 am. Then the chance of showers decreases.  At race time, 7 a.m., skies will be mostly cloudy.  The chances for rain will be about 50 % to 60%, but the biggest time frame for rain will be between 8 a.m. and 9 a.m. Computer models show a scattered shower moving through Sacramento towards the Foothills around that time. Otherwise, I expect most of the race to be on the drier side.

Sunday  Futurecast rain/snow models
KXTV

We didn't forget about the Sierra. More snowfall on the way through Sunday. Snow levels drop from 6,500 feet to 5,500 feet Saturday night into Sunday morning. Major passes like Lassen, Carson/Ebbetts ,and Sonora may see 3 to 4 feet of snowfall. Donner Pass may see up to 2.5 feet and Echo Pass, 1 to 1.5 feet of snow.

Futurecast snow accumulations
kxtv

A few scattered showers remain Sunday afternoon with thunderstorm chances, but the brunt of the system will be gone. Mostly cloudy skies to partly cloudy skies will remain for the week with temperatures in the mid to upper 50s.

RELATED:

Sacramento Local Forecast

Another 3 - 4 feet of snow possible at Lake Tahoe this weekend

First week of December starts with soggy Monday, multiple accidents in Northern California | Update

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