Contents
- Weather in September
- Frequently asked questions
- Average temperature in September
- Average pressure in September
- Average wind speed in September
- Average humidity in September
- Average rainfall in September
- Average rainfall days in September
- Average snowfall in September
- Average snowfall days in September
- Average daylight in September
- Average sunshine in September
- Average sunshine days in September
- Average UV index in September
- Average cloud cover in September
- Average visibility in September
Weather in September
Temperature
With the onset of September, Knoxville's average high-temperature slightly adjusts, moderately receding from August's hot 88.2°F (31.2°C) to a warm 82.2°F (27.9°C). Significant dips from daytime highs mark the September nights in Knoxville, with a consistent average temperature of 59.9°F (15.5°C).Heat index
The heat index in September is appraised at a tropical 87.8°F (31°C). Persistent activity under exposure might lead to a feeling of weariness, with subsequent heat cramps.Bear in mind that the heat index values are determined for shaded areas and light breezes. Exposure to unobstructed sunshine could lead to an increase in the heat index by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'felt air temperature' or 'apparent temperature', melds the effects of warmth and moisture to generate a feeling of heat. The impression of weather on a person can be swayed by additional aspects, including metabolic variations, pregnancy, and activity levels. You should know that direct sun exposure can heighten weather effects, potentially elevating the heat index by 15 Fahrenheit (8 Celsius) degrees. Heat index values are highly critical for babies and toddlers. Children often overlook the necessity for resting and fluid replenishment. Thirst is a late sign of dehydration - thus, it is critical to stay hydrated, especially during extended periods of physical activities.
Humidity
The average relative humidity in September is 72%.Rainfall
September is the month with the least rainfall. Rain falls for 11.3 days and accumulates 1.5" (38mm) of precipitation.Snowfall
In Knoxville, snow does not fall in May through October.Daylight
In Knoxville, the average length of the day in September is 12h and 23min.On the first day of September, sunrise is at 7:08 am and sunset at 8:02 pm. On the last day of the month, sunrise is at 7:30 am and sunset at 7:20 pm EDT.
Sunshine
In Knoxville, the average sunshine in September is 8.6h.UV index
The average daily maximum UV index in September is 5. A UV Index value of 3 to 5 symbolizes a medium health hazard from unsafe exposure to UV radiation for average individuals.Note: The daily high UV index of 5 during September translates into the following recommendations:
Act with care - The need to guard against sun damage is communicated. The mid-day Sun emits the most powerful UV radiation, so seek shade and minimize exposure. Clothes that are both tight-knit and comfortably loose are prime choices for sun protection.
Frequently asked questions
What are the temperatures in Knoxville in September?
What is the average humidity in September in Knoxville?
What is the driest month in Knoxville?
How many days does it rain in September in Knoxville?
When it does not snow in Knoxville?
What is the average length of the day in September in Knoxville?
When is the sunrise / sunset in September in Knoxville?
How long on average sun shines in September in Knoxville?
What is the UV index intensity in September in Knoxville?
Average temperature in September
Knoxville, TN
- Average high temperature in September: 82.2°F
The warmest month (with the highest average high temperature) is July (88.9°F).
The month with the lowest average high temperature is January (44.8°F).
- Average low temperature in September: 59.9°F
The month with the highest average low temperature is July (66.7°F).
The coldest month (with the lowest average low temperature) is January (29.3°F).
Average pressure in September
Knoxville, TN
- Average pressure in September: 30.04"Hg
The months with the highest atmospheric pressure are January and November (30.16"Hg).
The month with the lowest atmospheric pressure is June (29.98"Hg).
Average wind speed in September
Knoxville, TN
- Average wind speed in September: 4mph
The windiest month (with the highest average wind speed) is April (6mph).
The calmest month (with the lowest average wind speed) is August (3.8mph).
Average humidity in September
Knoxville, TN
- Average humidity in September: 72%
The months with the highest relative humidity are February and December (78%).
The month with the lowest relative humidity is August (70%).
Average rainfall in September
Knoxville, TN
- Average rainfall in September: 1.5"
The wettest month (with the highest rainfall) is February (3.66").
The driest month (with the least rainfall) is September (1.5").
Average rainfall days in September
Knoxville, TN
- Average rainfall days in September: 11.3 days
The month with the highest number of rainy days is July (16.2 days).
The month with the least rainy days is November (8.4 days).
Average snowfall in September
Knoxville, TN
- Average snowfall in September: 0"
The month with the highest snowfall is February (1.57").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in September
Knoxville, TN
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (3.8 days).
The months with the least snowfall days are May, June, July, August, September and October (0 days).
Average daylight in September /
Average sunshine in September
Knoxville, TN
- Average daylight in September: 12h and 2min
The month with the longest days is June (Average daylight: 14h and 36min).
The month with the shortest days is December (Average daylight: 9h and 48min).
- Average sunshine in September: 8h and 4min
The month with the most sunshine is June (Average sunshine: 10h and 36min).
The month with the least sunshine is January (Average sunshine: 4h and 54min).
Average sunshine days in September
Knoxville, TN
- Average sunshine days in September: 17.4 days
The month with the most sunshine days is October (20.5 days).
The month with the least sunshine days is July (12.9 days).
Average UV index in September
Knoxville, TN
- Average UV index in September: 5
The months with the highest UV index are May, June, July and August (UV index 6).
The months with the lowest UV index are January, February and December (UV index 2).
Average cloud cover in September
Knoxville, TN
- Average cloud cover in September: 30
The month with the most cloud cover is February (Cloud cover 54).
The month with the least cloud cover is June (Cloud cover 28).
Average visibility in September
Knoxville, TN
- Average visibility in September: 6mi
The months with the highest visibility are February, March, April, May, June, July, August, September, October, November and December (6mi).
The month with the lowest visibility is January (5mi).
Knoxville, Tennessee, USA
Weather forecast for your location
2. Allow the app to use your location
