Fallbrook Weather in January

What's the weather like in Fallbrook (California) in January 2026?

The climate in Fallbrook during January can be summarized as mild and reasonably dry.

January is in the winter in Fallbrook and is typically the coldest month of the year. Daytime maximum temperatures average around a cool 18°C (65°F), whilst at night 5°C (42°F) is normal.

Fallbrook weather averages (imperial / metric)
Daytime temperature 18.1°C 64.5°F
Nightly temperature 5.4°C 41.6°F
Average temperature 11.7°C 53.1°F
Daily sunshine 8.2 hrs
Avg rainfall 70 mm 2.8 ins
Rainy days 5 days
Sea temperature 14.9°C 58.8°F
Humidity 62%
Windspeed 11.2kph 7 mph

On average January is the wettest month of the year in Fallbrook with around 70mm 2.8 inches of rain making it a reasonably dry time to visit. This rainfall is typically spread over 5 days, although this may vary considerably.

On the flip side this corresponds to an average of 8.2 hours of sunshine per day.

January temperatures in Fallbrook

Fallbrook average temperature in January

January rainfall

Fallbrook average rain in January

January hourly sunshine

Fallbrook average rain in January

The data used in these monthly averages covers a period of over 100 years right up until last year. As such they are a valid prediction of what to expect for the weather in Fallbrook in January 2025.