Last updated: March 2, 2024
The weather in Boulder, United States, during August is characterized by an average temperature of 19°C (67°F). Highs can soar to 31°C (88°F), while lows may dip to 9°C (48°F). Typically, the humidity level in Boulder throughout August hovers around 56%.
Minimum temperature
Average temperature
Maximum temperature
Humidity
In August, Boulder averages 67 mm (2.7 inches) of rainfall, typically over the course of 13 rainy days. The month enjoys an average of 13 hours 39 minutes of daylight, with the sun shining for approximately 11 hours 19 minutes each day. Additionally, there is a 65% probability of sunny days during this period.
Precipitation
Rainy days
Sunshine hours
Chance of sun
In August, 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.
| 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 | 3 | 6 | 8 | 10 | 11 | 10 | 8 | 6 | 3 | 2 | 1 |
| Exposure | Low | Moderate | High | VeryHigh | Extreme | VeryHigh | High | Moderate | Low | ||||
| Time to burn | 45 min | 30 min | 25 min | 15 min | 10 min | 15 min | 25 min | 30 min | 45 min | ||||