January Weather in San Dimas, United States

Last updated: June 24, 2025

In January, the average temperature in San Dimas, United States hovers around 12°C (54°F), with a range that can drop to a chilly 2°C (36°F) or soar to a warm 30°C (86°F). Expect 80 mm (3.1 in) of precipitation spread over about 5 days, contributing to an average humidity level of 74%. Perfect for cozy days indoors or refreshingly cool outdoor adventures!

January Temperature in San Dimas

In January in San Dimas, the average temperature is 12°C (54°F). Maximum temperatures can reach up to 30°C (86°F), while minimums can drop as low as 2°C (36°F). This range makes it essential for travelers to pack both light clothing for the warmer days and warmer layers for cooler evenings.

January Weather in San Dimas: Daily Temperature Highs, Lows, and Averages

The chart illustrates January temperature patterns in San Dimas, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In San Dimas, January typically has an average temperature of 12°C (54°F), with highs reaching up to 30°C (86°F) and lows dropping to around 2°C (36°F).

Data source: Temperature data for San Dimas generated using information from the Copernicus Climate Change Service.

January Precipitation in San Dimas

In San Dimas in January, the precipitation amount is 80 mm (3.1 in) over a span of 5 days.

January Precipitation Trends in San Dimas

The chart displays monthly precipitation patterns in San Dimas, with values for each month alongside January’s data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how January’s conditions compare to those of other months. In San Dimas, January typically receives around 80 mm (3.1 inches) of precipitation spread over approximately 5 days.

Data source: Precipitation data for January generated using information from the Copernicus Climate Change Service.

Choose your preferred precipitation unit

Millimeters (mm) Inches (in)

January Humidity in San Dimas

In San Dimas in January, humidity is 74%. With an average temperature of 12°C (54°F), this humidity feels like a chilly embrace that can dampen your travel experience, making it essential to dress in layers and prepare for an unexpected drizzle while exploring the sights.

January Average Humidity in San Dimas

This chart illustrates the average monthly humidity levels in San Dimas, with January’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In January, average humidity in San Dimas is approximately 74%, offering insight into how humid the weather typically is during this month.

Data source: Humidity data for January generated using information from the Copernicus Climate Change Service.

January UV Index in San Dimas

In San Dimas in January, the maximum UV index reaches 4, which corresponds to a moderate Exposure Category. With a time to burn of 30 minutes, it’s important to take precautions to protect your skin. You can find more details in the Hourly UV Index in San Dimas for better planning.

Maximum UV Index Levels in San Dimas for January

The chart shows the monthly maximum UV Index (UVI) for San Dimas in January, representing the highest UV radiation level. The UVI measures the intensity of ultraviolet radiation from the sun, indicating the potential risk of sunburn and UV-related health issues. In January, the maximum UV index in San Dimas typically reaches 4, which falls under the moderate exposure category.

Data source: San Dimas January UVI data generated using information from the Copernicus Climate Change Service.

UV Risk Categories

Extreme (11+): Avoid the sun, stay in shade.
Very High (8-10): Limit sun exposure.
High (6-7): Use SPF 30+ and protective clothing.
Moderate (3-5): Midday shade recommended.
Low (0-2): No protection needed.

How January Weather in San Dimas Compares to Other Months

Weather in San Dimas varies notably across the year, with each month offering distinct climate conditions. This page compares January’s weather to other months in San Dimas, focusing on differences in temperature, rainfall, humidity, and UV levels.

This table compares monthly weather conditions in San Dimas, showing how January’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	12°C (54°F)	80 mm (3.1 inches)	74%	moderate
February Weather	12°C (55°F)	70 mm (2.8 inches)	79%	high
March Weather	14°C (57°F)	76 mm (3.0 inches)	75%	very high
April Weather	16°C (62°F)	27 mm (1.1 inches)	70%	very high
May Weather	18°C (64°F)	17 mm (0.7 inches)	70%	very high
June Weather	21°C (70°F)	1 mm (0.0 inches)	72%	extreme
July Weather	24°C (76°F)	1 mm (0.1 inches)	73%	extreme
August Weather	25°C (77°F)	2 mm (0.1 inches)	69%	very high
September Weather	23°C (74°F)	3 mm (0.1 inches)	68%	very high
October Weather	20°C (68°F)	12 mm (0.5 inches)	67%	high
November Weather	16°C (61°F)	26 mm (1.0 inches)	68%	moderate
December Weather	12°C (54°F)	79 mm (3.1 inches)	71%	moderate