With a population of around 1,400, Janesville sits in California, United States. The city operates in the Pacific Time Zone.
In 2025, Janesville recorded an average annual temperature of 53°F. The hottest temperatures reached 102°F in July; the coolest were 3°F in February. Total precipitation for the year was 30 inches, with the wettest month being February. Snowfall for the year totaled approximately 21 inches.
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