San Dimas (CA) Weather & Climate: Best Time to Visit

Average temperatures, rainfall, sunshine and the best time to visit San Dimas.

Climate overview of San Dimas

San Dimas, California, United States of America, experiences significant temperature variation throughout the year. Summers bring daytime highs of 33°C (91°F) in August, while winters cool to 19°C (66°F) in December.

Rainfall is modest, totalling around 344 mm (14 in) annually. The city experiences a distinct dry season from April to November. December tends to be the wettest month. The most sunshine falls in July, with an average of 12.3 hours of daily sunshine.

San Dimas Weather by Month

Pick a month to see the average temperature, rainfall and sunshine in San Dimas — and find the best time to visit.

Monthly Temperature in San Dimas

Depending on the time of the year, temperatures range from very warm to pleasant in San Dimas. Average maximum daytime temperatures range from a very warm 33°C (91°F) in August, the warmest time of the year, to a pleasant 19°C (66°F) during cooler months like December.

At night, you can expect temperatures ranging from 17°C (63°F) in August to around 6°C (43°F) during December.

Check out our detailed temperature page for more information.

Temperature ranges by month

Rainfall in San Dimas

With annual rainfall averaging 344 mm (14 in), San Dimas maintains relatively low precipitation levels throughout the seasons. Significant seasonal changes in precipitation occur throughout the year. In the wettest month, December it receives moderate rainfall, averaging 93 mm (3.7 in) of precipitation, recorded across 9 rainy days. In contrast, the driest month June brings less rainfall, with 0.2 mm (0.01 in) over 0 rainy days. For more details, please visit our San Dimas Precipitation page.

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

Sunshine Hours in San Dimas

Seasonal changes in sunshine hours are quite dramatic in San Dimas. While July receives considerable daily sunshine with up to 12.3 hours, January marks the darkest time of the year, where sunshine is scarce with only 6.6 hours of sunlight per day.

Visit our detailed sunshine hours page for more information.

Monthly hours of sunshine

Data from: Corona, the United States of America (33 KM, 21 Miles).

Daily hours of sunshine

Data from: Corona, the United States of America (33 KM, 21 Miles).

Best Time to Visit San Dimas

During the months of January, February, March, April, May and November, San Dimas enjoys pleasant weather with average temperatures ranging from 20°C (68°F) to 26°C (78°F). These months are perfect for sightseeing and exploring.

Rainfall during this time ranges from 10 mm (0.4 in) in May to 66 mm (2.6 in) in February. This means you can expect a mix of sunny days and occasional showers.

Seeking the perfect travel destination for this year? We've created a tool that suggests locations matching your desired weather. Let our weather planner guide your travel decisions.

Frequently asked questions about the climate in San Dimas

What is the best time to visit San Dimas?

January, February, March, April, May, October and November typically offer the most optimal weather in San Dimas. In contrast, July and August tend to have less optimal conditions. San Dimas has a distinct dry season from April to November.

What temperatures can I expect in San Dimas?

Daytime highs range from 19°C (66°F) in December to 33°C (91°F) in August. Nighttime lows range from 6°C (43°F) to 17°C (63°F). Temperatures vary considerably through the year.

How much rain does San Dimas get?

Annual rainfall is around 344 mm (14 in). December is the wettest month with 93 mm (3.7 in), while June is the driest with 0.2 mm (0.01 in).

How sunny is San Dimas?

San Dimas receives around 3,279 hours of sunshine per year. July is the sunniest month with 369 hours, while January is the cloudiest with just 198 hours. Overall, San Dimas enjoys abundant sunshine.

San Dimas 3-Day Forecast

San Dimas (CA) 3-Day Forecast

San Dimas on the map

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