With a population of around 14,900, Johnstown sits in Colorado, United States. The city operates in the Mountain Time Zone.
In 2025, Johnstown recorded an average annual temperature of 51°F. The hottest temperatures reached 100°F in August; the coolest were -15°F in January. Total precipitation for the year was 16 inches, with the wettest month being May. Snowfall for the year totaled approximately 8 inches.
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