Monrovia (CA) Weather & Climate: Best Time to Visit

The climate in Monrovia is known for significant temperature differences throughout the year, making the weather dynamic. On average, daytime temperatures range from a very warm 34°C (93°F) in August to a pleasant 19°C (66°F) in December.

Nighttime temperatures range from 18°C (64°F) in August to 8°C (46°F) in December.

Check out our detailed temperature page for more information.

Temperature ranges by month

Monrovia has a relatively dry climate with low precipitation, averaging 417 mm (16 in) of rainfall annually. The seasons in Monrovia bring significant changes in precipitation. The wettest month, December, receives moderate rainfall, with an average of 98 mm (3.9 in) of precipitation. This rainfall is distributed across 9 rainy days.

In contrast, the driest month, August, experiences much less rainfall, totaling 0.4 mm (0.02 in) over 0 rainy days. These distinct seasonal differences provide diverse experiences throughout the year. For more details, please visit our Monrovia Precipitation page.

The mean monthly precipitation over the year, including rain, hail, and snow

The average number of days each month with precipitation

In Monrovia, summer days are longer and more sunny, with daily sunshine hours peaking at 12.1 hours in July. As the darker season arrives, the brightness of the sun becomes less. November sees a soft sun for only 7.2 hours per average day.

Visit our detailed sunshine hours page for more information.

Monthly hours of sunshine

Daily hours of sunshine

Daily percentage of sunshine

The relative humidity is high throughout the year in Monrovia.

The city experiences its highest humidity in May, reaching 73%. In November, the humidity drops to its lowest level at 50%. What does this mean? Read our detailed page on humidity levels for further details.

Relative humidity over the year