Atmospheric River Bringing Heavy Rain to Southern California and Heavy Snow to the Sierra Nevadas

A strong atmospheric river will continue heavy rain over southern California through Friday. The heaviest rainfall is ongoing today in the Los Angeles Basin. Flash and urban flooding is possible. A prolonged heavy snowfall has begun over the Sierra Nevada Mountains and will continue through Friday. Travel will become increasingly difficult over the passes due to snow and strong winds. Read More >

Hazardous Weather Conditions

Flood Watch until December 26, 10:00 PM PST

Current conditions at

SJSU - Mount Diablo Summit Museum Rooftop (SJS02)

Lat: 37.881699°NLon: 121.914173°WElev: 3904.0ft.

41°F

5°C

Humidity	100%
Wind Speed	S 21 MPH
Barometer	NA
Dewpoint	41°F (5°C)
Visibility	NA
Wind Chill	32°F (0°C)
Last update	25 Dec 05:50 PM PST

More Information:

Local Forecast Office More Local Wx 3 Day History Hourly Weather Forecast

Extended Forecast for

3 Miles S Clayton CA

Flood Watch December 25, 06:06pm until December 26, 10:00pm

Click here for hazard details and duration

Flood Watch

Flood Watch December 25, 06:06pm until December 26, 10:00pm
NOW until 10:00pm Fri
Flood Watch
Tonight
Low: 47 °F
Breezy.
Severe
Thunderstorms
then Chance
Showers
Friday
High: 49 °F
Showers
Likely
Friday Night
Low: 41 °F
Chance
Showers
Saturday
High: 48 °F
Slight Chance
Showers then
Mostly Sunny
Saturday Night
Low: 38 °F
Mostly Clear
Sunday
High: 47 °F
Sunny
Sunday Night
Low: 37 °F
Mostly Clear
Monday
High: 48 °F
Sunny

Detailed Forecast

Tonight

Showers and possibly a thunderstorm before 10pm, then showers likely. Some of the storms could be severe. Steady temperature around 47. Breezy, with a south southwest wind 20 to 22 mph, with gusts as high as 38 mph. Chance of precipitation is 90%. New precipitation amounts between a half and three quarters of an inch possible.

Friday

Showers likely, with thunderstorms also possible after 4pm. Mostly cloudy, with a high near 49. South wind 11 to 18 mph, with gusts as high as 34 mph. Chance of precipitation is 60%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.

Friday Night

A chance of showers and thunderstorms. Mostly cloudy, with a low around 41. South southwest wind around 9 mph. Chance of precipitation is 40%. New precipitation amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.

Saturday

A 20 percent chance of showers before 10am. Mostly sunny, with a high near 48. North wind around 7 mph.

Saturday Night

Mostly clear, with a low around 38. Northwest wind around 6 mph.

Sunday

Sunny, with a high near 47.

Sunday Night

Mostly clear, with a low around 37.

Monday

Sunny, with a high near 48.

Monday Night

Mostly clear, with a low around 38.