National Weather Service Forecast for: 4 Miles S Rialto CA
Issued by: National Weather Service San Diego, CA
Updated: 12:35 pm PST Dec 22, 2025
 
Tonight

Tonight: Patchy fog after 4am.  Otherwise, mostly cloudy, with a low around 51. Southwest wind around 5 mph becoming calm.
Mostly Cloudy
then Patchy
Fog
Tuesday

Tuesday: A chance of showers, mainly after 4pm.  Patchy fog before 10am.  Otherwise, mostly cloudy, with a high near 67. Light southeast wind increasing to 5 to 10 mph in the morning.  Chance of precipitation is 30%.
Chance
Showers and
Patchy Fog
Tuesday
Night
Tuesday Night: Showers, mainly after 10pm. The rain could be heavy at times.  Low around 54. Light east wind becoming southeast 10 to 15 mph after midnight. Winds could gust as high as 20 mph.  Chance of precipitation is 90%. New precipitation amounts between three quarters and one inch possible.
Heavy Rain

Wednesday

Wednesday: Showers, with thunderstorms also possible after 10am. Some of the storms could produce heavy rainfall.  High near 64. South wind 10 to 20 mph, with gusts as high as 30 mph.  Chance of precipitation is 100%. New rainfall amounts between 2 and 3 inches possible.
Heavy Rain

Wednesday
Night
Wednesday Night: Showers and possibly a thunderstorm. Some of the storms could produce heavy rainfall.  Low around 53. Southwest wind 5 to 10 mph becoming light and variable. Winds could gust as high as 20 mph.  Chance of precipitation is 100%. New rainfall amounts between a quarter and half of an inch possible.
Heavy Rain

Christmas
Day
Christmas Day: Showers.  High near 64. Chance of precipitation is 80%.
Showers

Thursday
Night
Thursday Night: Showers.  Low around 50. Chance of precipitation is 90%.
Showers

Friday

Friday: Showers.  Mostly cloudy, with a high near 61.
Showers

Friday
Night
Friday Night: Showers likely, mainly before 10pm.  Mostly cloudy, with a low around 43.
Showers
Likely
Lo 51 °F Hi 67 °F Lo 54 °F Hi 64 °F Lo 53 °F Hi 64 °F Lo 50 °F Hi 61 °F Lo 43 °F

Flood Watch
Wind Advisory
 

Tonight
 
Patchy fog after 4am. Otherwise, mostly cloudy, with a low around 51. Southwest wind around 5 mph becoming calm.
Tuesday
 
A chance of showers, mainly after 4pm. Patchy fog before 10am. Otherwise, mostly cloudy, with a high near 67. Light southeast wind increasing to 5 to 10 mph in the morning. Chance of precipitation is 30%.
Tuesday Night
 
Showers, mainly after 10pm. The rain could be heavy at times. Low around 54. Light east wind becoming southeast 10 to 15 mph after midnight. Winds could gust as high as 20 mph. Chance of precipitation is 90%. New precipitation amounts between three quarters and one inch possible.
Wednesday
 
Showers, with thunderstorms also possible after 10am. Some of the storms could produce heavy rainfall. High near 64. South wind 10 to 20 mph, with gusts as high as 30 mph. Chance of precipitation is 100%. New rainfall amounts between 2 and 3 inches possible.
Wednesday Night
 
Showers and possibly a thunderstorm. Some of the storms could produce heavy rainfall. Low around 53. Southwest wind 5 to 10 mph becoming light and variable. Winds could gust as high as 20 mph. Chance of precipitation is 100%. New rainfall amounts between a quarter and half of an inch possible.
Christmas Day
 
Showers. High near 64. Chance of precipitation is 80%.
Thursday Night
 
Showers. Low around 50. Chance of precipitation is 90%.
Friday
 
Showers. Mostly cloudy, with a high near 61.
Friday Night
 
Showers likely, mainly before 10pm. Mostly cloudy, with a low around 43.
Saturday
 
A slight chance of showers. Mostly sunny, with a high near 62.
Saturday Night
 
A slight chance of showers. Partly cloudy, with a low around 42.
Sunday
 
Sunny, with a high near 64.
Sunday Night
 
Partly cloudy, with a low around 43.
Monday
 
A slight chance of showers. Mostly sunny, with a high near 67.

 

Forecast from NOAA-NWS for 4 Miles S Rialto CA.