April Weather in Boulder

Last updated: March 2, 2024

The weather in Boulder, United States, during April is characterized by an average temperature of 5°C (42°F). Highs can soar to 22°C (72°F), while lows may dip to -11°C (13°F). Typically, the humidity level in Boulder throughout April hovers around 76%.

-11°C (13°F)

Minimum temperature

5°C (42°F)

Average temperature

22°C (72°F)

Maximum temperature

76%

Humidity

Precipitation and Sunshine hours

In April, Boulder averages 68 mm (2.7 inches) of rainfall, typically over the course of 12 rainy days. The month enjoys an average of 13 hours 18 minutes of daylight, with the sun shining for approximately 10 hours 7 minutes each day. Additionally, there is a 51% probability of sunny days during this period.

68 mm (2.7 inches)

Precipitation

12 rainy days

Rainy days

10 hours 7 minutes

Sunshine hours

51%

Chance of sun

UV Index

In April, the UV Index in Boulder reaches a maximum of 11, indicating a level of Extreme exposure. The most intense UV radiation typically occurs between 13:00 and 15:00, during which unprotected skin may burn in as little as 10 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 1 2 4 6 9 10 11 10 8 5 3 1 1
Exposure Low Moderate High VeryHigh Extreme VeryHigh Moderate Low
Time to burn 45 min 30 min 25 min 15 min 10 min 15 min 30 min 45 min

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