September weather forecastRock Island, TN
September
Weather in September
September, the first month of the autumn in Rock Island, is still a warm month, with an average temperature fluctuating between 79.7°F (26.5°C) and 59.9°F (15.5°C).Temperature
The transition into September shows a subtle variation to a still moderately hot 79.7°F (26.5°C) from August's 84.9°F (29.4°C) in the average high-temperature. September brings with it a nighttime average temperature of 59.9°F (15.5°C).Humidity
In September, the average relative humidity is 77%.Rainfall
In Rock Island, in September, during 14.5 rainfall days, 1.89" (48mm) of precipitation is typically accumulated. Throughout the year, there are 177.3 rainfall days, and 31.02" (788mm) of precipitation is accumulated.Snowfall
In Rock Island, snow does not fall in May through October.Daylight
In Rock Island, the average length of the day in September is 12h and 23min.On the first day of September in Rock Island, Tennessee, sunrise is at 6:15 am and sunset at 7:09 pm. On the last day of the month, sunrise is at 6:37 am and sunset at 6:27 pm CDT.
Sunshine
In September, the average sunshine is 8.2h.UV index
The average daily maximum UV index in September in Rock Island, Tennessee, is 5. A UV Index value of 3 to 5 symbolizes a moderate threat to health from exposure to the Sun's UV rays for ordinary individuals.Note: The maximum daily UV index of 5 during September translates into the following directions:
Exercise prevention - Warding off sunburn is urged. The Sun's radiation is especially intense around midday; try to stay in shade during this period. Enhance your sun protection with tightly woven, yet airy clothing.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Rock Island, TN
- Average high temperature in September: 79.7°F
The warmest month (with the highest average high temperature) is July (86°F).
The month with the lowest average high temperature is January (44.2°F).
- Average low temperature in September: 59.9°F
The month with the highest average low temperature is July (65.8°F).
The coldest month (with the lowest average low temperature) is January (29.8°F).
Average pressure in September
Rock Island, TN
- Average pressure in September: 30.03"Hg
The month with the highest atmospheric pressure is January (30.17"Hg).
The month with the lowest atmospheric pressure is June (29.98"Hg).
Average wind speed in September
Rock Island, TN
- Average wind speed in September: 4.5mph
The windiest month (with the highest average wind speed) is February (7.4mph).
The calmest month (with the lowest average wind speed) is August (4.2mph).
Average humidity in September
Rock Island, TN
- Average humidity in September: 77%
The month with the highest relative humidity is December (81%).
The months with the lowest relative humidity are October and November (76%).
Average rainfall in September
Rock Island, TN
- Average rainfall in September: 1.89"
The wettest month (with the highest rainfall) is July (3.82").
The driest month (with the least rainfall) is November (1.65").
Average rainfall days in September
Rock Island, TN
- Average rainfall days in September: 14.5 days
The month with the highest number of rainy days is July (20.9 days).
The month with the least rainy days is November (9.3 days).
Average snowfall in September
Rock Island, TN
- Average snowfall in September: 0"
The month with the highest snowfall is February (0.51").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in September
Rock Island, TN
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (3.6 days).
The months with the least snowfall days are May, June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Rock Island, TN
- Average daylight in September: 12h and 24min
The month with the longest days is June (Average daylight: 14h and 30min).
The month with the shortest days is December (Average daylight: 9h and 48min).
- Average sunshine in September: 8h and 12min
The month with the most sunshine is June (Average sunshine: 10h and 30min).
The month with the least sunshine is February (Average sunshine: 4h and 24min).
Average sunshine days in September
Rock Island, TN
- Average sunshine days in September: 13.3 days
The month with the most sunshine days is November (18.5 days).
The month with the least sunshine days is July (8.4 days).
Average UV index in September
Rock Island, 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 and December (UV index 2).
Average cloud cover in September
Rock Island, TN
- Average cloud cover in September: 33
The month with the most cloud cover is February (Cloud cover 54).
The month with the least cloud cover is June (Cloud cover 30).
Average visibility in September
Rock Island, TN
- Average visibility in September: 5mi
The months with the highest visibility are February, April, June, October and November (6mi).
The months with the lowest visibility are January, March, May, July, August, September and December (5mi).





