Last updated: March 2, 2024
The weather in Mount Vernon, United States, during September is characterized by an average temperature of 15°C (59°F). Highs can soar to 26°C (78°F), while lows may dip to 7°C (45°F). Typically, the humidity level in Mount Vernon throughout September hovers around 76%.
Minimum temperature
Average temperature
Maximum temperature
Humidity
In September, Mount Vernon averages 146 mm (5.8 inches) of rainfall, typically over the course of 12 rainy days. The month enjoys an average of 12 hours 30 minutes of daylight, with the sun shining for approximately 8 hours 47 minutes each day. Additionally, there is a 31% probability of sunny days during this period.
Precipitation
Rainy days
Sunshine hours
Chance of sun
In September, the UV Index in Mount Vernon reaches a maximum of 7, indicating a level of High exposure. The most intense UV radiation typically occurs between 13:00 and 15:00, during which unprotected skin may burn in as little as 25 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 | 1 | 2 | 3 | 5 | 6 | 7 | 6 | 5 | 4 | 2 | 1 | 1 |
| Exposure | Low | Moderate | High | Moderate | Low | ||||||||
| Time to burn | 45 min | 30 min | 25 min | 30 min | 45 min | ||||||||