National Weather Service Forecast for: Fallbrook CA
Issued by: National Weather Service San Diego, CA
Updated: 12:34 am PDT Aug 20, 2026
 
Overnight

Overnight: Mostly clear, with a low around 65. Calm wind.
Mostly Clear

 Thursday

Thursday: Patchy fog before 11am. Otherwise, mostly sunny, with a high near 89. Light and variable wind becoming southwest 10 to 15 mph in the morning. Winds could gust as high as 20 mph.
Patchy Fog
then Mostly
Sunny
 Thursday
Night
Thursday Night: Mostly clear, with a low around 66. Southwest wind around 5 mph becoming calm in the evening.
Mostly Clear

 Friday

Friday: Sunny, with a high near 89. Light southwest wind increasing to 10 to 15 mph in the morning. Winds could gust as high as 20 mph.
Sunny

 Friday
Night
Friday Night: Mostly clear, with a low around 66. West wind around 5 mph becoming calm.
Mostly Clear

 Saturday

Saturday: Patchy fog before 11am. Otherwise, sunny, with a high near 90.
Patchy Fog
then Sunny
 Saturday
Night
Saturday Night: Mostly clear, with a low around 67.
Mostly Clear

 Sunday

Sunday: Patchy fog before 11am. Otherwise, sunny, with a high near 91.
Patchy Fog
then Sunny
 Sunday
Night
Sunday Night: Mostly clear, with a low around 66.
Mostly Clear
Lo 65 °F Hi 89 °F Lo 66 °F Hi 89 °F Lo 66 °F Hi 90 °F Lo 67 °F Hi 91 °F Lo 66 °F

 

Overnight
 
 Mostly clear, with a low around 65. Calm wind.
Thursday
 
 Patchy fog before 11am. Otherwise, mostly sunny, with a high near 89. Light and variable wind becoming southwest 10 to 15 mph in the morning. Winds could gust as high as 20 mph.
Thursday Night
 
 Mostly clear, with a low around 66. Southwest wind around 5 mph becoming calm in the evening.
Friday
 
 Sunny, with a high near 89. Light southwest wind increasing to 10 to 15 mph in the morning. Winds could gust as high as 20 mph.
Friday Night
 
 Mostly clear, with a low around 66. West wind around 5 mph becoming calm.
Saturday
 
 Patchy fog before 11am. Otherwise, sunny, with a high near 90.
Saturday Night
 
 Mostly clear, with a low around 67.
Sunday
 
 Patchy fog before 11am. Otherwise, sunny, with a high near 91.
Sunday Night
 
 Mostly clear, with a low around 66.
Monday
 
 Sunny, with a high near 92.
Monday Night
 
 Mostly clear, with a low around 67.
Tuesday
 
 Sunny, with a high near 93.
Tuesday Night
 
 Mostly clear, with a low around 68.
Wednesday
 
 Sunny, with a high near 93.

 

Forecast from NOAA-NWS for Fallbrook CA.