January Weather in Walnut Creek, United States

Last updated: June 24, 2025

In January, the average temperature in Walnut Creek, United States hovers around 8°C (47°F). While you might experience a chilly minimum of -5°C (24°F), the thermometers can also rise to a pleasant 21°C (71°F) on milder days. With an average precipitation of 28 mm (1.1 in) spread over 4 days, and a humidity level of 77%, packing for both warmth and a possible shower is wise.

January Temperature in Walnut Creek

In January in Walnut Creek, the average temperature is 8°C (47°F). Maximums can reach 21°C (71°F), and minimums can be as low as -5°C (24°F). This varied climate makes it an ideal time to pack layers for your travels.

January Weather in Walnut Creek: Daily Temperature Highs, Lows, and Averages

The chart illustrates January temperature patterns in Walnut Creek, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Walnut Creek, January typically has an average temperature of 8°C (47°F), with highs reaching up to 21°C (71°F) and lows dropping to around -5°C (24°F).

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

January Precipitation in Walnut Creek

In Walnut Creek in January, the precipitation amount is 28 mm (1.1 in) over the course of 4 days.

January Precipitation Trends in Walnut Creek

The chart displays monthly precipitation patterns in Walnut Creek, 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 Walnut Creek, January typically receives around 28 mm (1.1 inches) of precipitation spread over approximately 4 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 Walnut Creek

In Walnut Creek in January, humidity is 77%. With an average temperature of 8°C (47°F), this humidity feels like a damp chill that can make even short walks outside feel uncomfortable, often clinging to your skin and making you long for warmer, drier conditions.

January Average Humidity in Walnut Creek

This chart illustrates the average monthly humidity levels in Walnut Creek, 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 Walnut Creek is approximately 77%, 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 Walnut Creek

In Walnut Creek 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 Walnut Creek for better planning.

Maximum UV Index Levels in Walnut Creek for January

The chart shows the monthly maximum UV Index (UVI) for Walnut Creek 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 Walnut Creek typically reaches 4, which falls under the moderate exposure category.

Data source: Walnut Creek 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 Walnut Creek Compares to Other Months

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

This table compares monthly weather conditions in Walnut Creek, showing how January’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	8°C (47°F)	28 mm (1.1 inches)	77%	moderate
February Weather	10°C (49°F)	29 mm (1.1 inches)	80%	high
March Weather	13°C (56°F)	36 mm (1.4 inches)	68%	very high
April Weather	19°C (67°F)	8 mm (0.3 inches)	58%	very high
May Weather	23°C (74°F)	7 mm (0.3 inches)	45%	extreme
June Weather	30°C (86°F)	1 mm (0.1 inches)	31%	extreme
July Weather	32°C (89°F)	32 mm (1.3 inches)	27%	extreme
August Weather	32°C (89°F)	14 mm (0.6 inches)	30%	extreme
September Weather	27°C (81°F)	15 mm (0.6 inches)	48%	very high
October Weather	19°C (67°F)	20 mm (0.8 inches)	59%	high
November Weather	14°C (57°F)	26 mm (1.0 inches)	70%	moderate
December Weather	8°C (47°F)	21 mm (0.8 inches)	77%	moderate