January Weather in Boulder

Last updated: March 2, 2024

The weather in Boulder, United States, during January is characterized by an average temperature of -8°C (18°F). Highs can soar to 3°C (37°F), while lows may dip to -24°C (-11°F). Typically, the humidity level in Boulder throughout January hovers around 87%.

-24°C (-11°F)

Minimum temperature

-8°C (18°F)

Average temperature

3°C (37°F)

Maximum temperature

87%

Humidity

Precipitation and Sunshine hours

In January, Boulder averages 23 mm (0.9 inches) of rainfall, typically over the course of 7 rainy days. The month enjoys an average of 9 hours 4 minutes of daylight, with the sun shining for approximately 4 hours 47 minutes each day. Additionally, there is a 35% probability of sunny days during this period.

23 mm (0.9 inches)

Precipitation

7 rainy days

Rainy days

4 hours 47 minutes

Sunshine hours

35%

Chance of sun

UV Index

In January, the UV Index in Boulder reaches a maximum of 3, indicating a level of Moderate exposure. The most intense UV radiation typically occurs between 12:00 and 14:00, during which unprotected skin may burn in as little as 30 minutes.

Average solar exposure data for the current time of the year. Actual values may vary and depend on many factors, such as cloud cover, vegetation cover, surface type, etc.
  07:00 08:00 09:00 10:00 11:00 12:00 13:00 14:00 15:00 16:00 17:00 18:00 19:00
UVI 0 1 1 1 2 3 3 2 2 1 1 0 0
Exposure Low Moderate Low
Time to burn 45 min 30 min 45 min

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