Last updated: June 24, 2025
In September, the average temperature in Jefferson, United States hovers around 21°C (69°F), with a minimum dipping to 5°C (41°F) and a maximum soaring to 33°C (92°F). Expect around 123 mm (4.9 in) of precipitation over approximately 10 days, contributing to an average humidity of 75%. Whether you're planning outdoor adventures or cozy indoor activities, be prepared for a mix of weather!
In September in Jefferson, the average temperature is 21°C (69°F). Maximum temperatures can reach 33°C (92°F), while minimums can drop to as low as 5°C (41°F). This diverse climate makes Jefferson an ideal destination for travelers seeking both warm days and cooler evenings.
In Jefferson in September, the total precipitation amount is 123 mm (4.9 in) over the course of 10 days.
In Jefferson in September, humidity is 75%. With an average temperature of 21°C (69°F), this humidity feels like a warm, sticky embrace that can make even a short walk feel exhausting for travelers, often leading to a longing for refreshing breezes or air-conditioned retreats.
In Jefferson in September, the maximum UV index is 8, which corresponds to a very high Exposure Category. This means that the time to burn is only 15 minutes. For more detailed information, you can refer to the Hourly UV Index in Jefferson.
UV Risk Categories
Weather in Jefferson varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Jefferson, focusing on differences in temperature, rainfall, humidity, and UV levels.
| Temperature | Precipitation | Humidity | UV | |
|---|---|---|---|---|
| January Weather | 1°C (34°F) | 60 mm (2.4 inches) | 84% | moderate |
| February Weather | 3°C (38°F) | 97 mm (3.8 inches) | 83% | moderate |
| March Weather | 6°C (44°F) | 96 mm (3.8 inches) | 83% | high |
| April Weather | 12°C (54°F) | 100 mm (4.0 inches) | 81% | very high |
| May Weather | 18°C (64°F) | 139 mm (5.5 inches) | 78% | very high |
| June Weather | 22°C (73°F) | 115 mm (4.5 inches) | 79% | very high |
| July Weather | 25°C (78°F) | 145 mm (5.7 inches) | 74% | very high |
| August Weather | 24°C (75°F) | 148 mm (5.8 inches) | 72% | very high |
| September Weather | 21°C (69°F) | 123 mm (4.9 inches) | 75% | very high |
| October Weather | 15°C (60°F) | 103 mm (4.1 inches) | 81% | high |
| November Weather | 7°C (45°F) | 90 mm (3.6 inches) | 85% | moderate |
| December Weather | 3°C (38°F) | 93 mm (3.6 inches) | 84% | moderate |