September Weather in Knoxville

Last updated: March 2, 2024

The weather in Knoxville, United States, during September is characterized by an average temperature of 25°C (78°F). Highs can soar to 35°C (96°F), while lows may dip to 14°C (58°F). Typically, the humidity level in Knoxville throughout September hovers around 82%.

14°C (58°F)

Minimum temperature

25°C (78°F)

Average temperature

35°C (96°F)

Maximum temperature

82%

Humidity

Precipitation and Sunshine hours

In September, Knoxville averages 96 mm (3.8 inches) of rainfall, typically over the course of 8 rainy days. The month enjoys an average of 12 hours 19 minutes of daylight, with the sun shining for approximately 9 hours 53 minutes each day. Additionally, there is a 45% probability of sunny days during this period.

96 mm (3.8 inches)

Precipitation

8 rainy days

Rainy days

9 hours 53 minutes

Sunshine hours

45%

Chance of sun

UV Index

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

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