National Oceanic and Atmospheric Administration National Weather Service United States Department of Commerce

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

Current conditions at

Hayward, Hayward Air Terminal (KHWD)

Lat: 37.66083°NLon: 122.11833°WElev: 46.0ft.

Rain

52°F

11°C

Humidity 87%
Wind Speed SE 9 MPH
Barometer 29.89 in (1012.19 mb)
Dewpoint 48°F (9°C)
Visibility 10.00 mi
Last update 26 Dec 02:00 AM PST
Extended Forecast for

San Lorenzo CA

Flood Watch December 26, 02:27am until December 26, 10:00pm
Click here for hazard details and duration
Flood Watch
  •  
    Flood Watch December 26, 02:27am until December 26, 10:00pm

    NOW until 10:00pm Fri

    Flood Watch

  • Overnight

    Low: 50 °F

    Chance
    Showers

  • Friday

    Friday: Showers likely, with thunderstorms also possible after 4pm. Mostly cloudy, with a high near 57. South southeast wind 13 to 15 mph, with gusts as high as 24 mph. Chance of precipitation is 60%. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.

    High: 57 °F

    Showers
    Likely

  • Friday Night

    Friday Night: A chance of showers and thunderstorms. Mostly cloudy, with a low around 46. South wind 6 to 8 mph. Chance of precipitation is 50%. New precipitation amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.

    Low: 46 °F

    Chance
    Showers

  • Saturday

    Saturday: A 20 percent chance of showers before 10am. Mostly sunny, with a high near 54. North wind 6 to 8 mph.

    High: 54 °F

    Slight Chance
    Showers then
    Mostly Sunny

  • Saturday Night

    Saturday Night: Mostly clear, with a low around 39. Northeast wind 3 to 6 mph.

    Low: 39 °F

    Mostly Clear

  • Sunday

    Sunday: Sunny, with a high near 54.

    High: 54 °F

    Sunny

  • Sunday Night

    Sunday Night: Mostly clear, with a low around 37.

    Low: 37 °F

    Mostly Clear

  • Monday

    Monday: Sunny, with a high near 55.

    High: 55 °F

    Sunny

Detailed Forecast

Overnight
A 40 percent chance of showers. Mostly cloudy, with a low around 50. South wind around 14 mph, with gusts as high as 24 mph. New precipitation amounts of less than a tenth of an inch possible.
Friday
Showers likely, with thunderstorms also possible after 4pm. Mostly cloudy, with a high near 57. South southeast wind 13 to 15 mph, with gusts as high as 24 mph. Chance of precipitation is 60%. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.
Friday Night
A chance of showers and thunderstorms. Mostly cloudy, with a low around 46. South wind 6 to 8 mph. Chance of precipitation is 50%. 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 54. North wind 6 to 8 mph.
Saturday Night
Mostly clear, with a low around 39. Northeast wind 3 to 6 mph.
Sunday
Sunny, with a high near 54.
Sunday Night
Mostly clear, with a low around 37.
Monday
Sunny, with a high near 55.
Monday Night
Mostly clear, with a low around 38.
Tuesday
Sunny, with a high near 57.
Tuesday Night
Mostly clear, with a low around 40.
Wednesday
Mostly sunny, with a high near 57.
Wednesday Night
A slight chance of showers. Partly cloudy, with a low around 43.
New Year's Day
A chance of showers. Partly sunny, with a high near 56.
Basemap Options
Click map to change the forecast location
Loading map...
Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
San Lorenzo CA
 37.66°N 122.12°W (Elev. 66 ft)
Last Update:
12:27 am PST Dec 26, 2025
Forecast Valid:
2am PST Dec 26, 2025-6pm PST Jan 1, 2026
 
Forecast Discussion
 
Get as KML Get as XML

Additional Resources

Radar & Satellite Image

Link to Local Radar Data Link to Satellite Data

Hourly Weather Forecast

National Digital Forecast Database

National Digital Forecast Database Maximum Temperature Forecast

High Temperature

National Digital Forecast Database Weather Element Forecast

Chance of Precipitation