September weather forecastBristol, SD
September
Weather in September
September, the first month of the autumn in Bristol, is also an agreeable month, with an average temperature varying between 71.6°F (22°C) and 51.3°F (10.7°C).Temperature
September witnesses a gentle descent in average high-temperature, descending from August's warm 80.1°F (26.7°C) to an agreeable 71.6°F (22°C). An average temperature of 51.3°F (10.7°C) is recorded during the nights in September.Humidity
September is the least humid month, with an average relative humidity of 66%.Rainfall
In September, the rain falls for 10.1 days. Throughout September, 1.57" (40mm) of precipitation is accumulated. Throughout the year, there are 112.9 rainfall days, and 22.09" (561mm) of precipitation is accumulated.Snowfall
June through September are months without snowfall.Daylight
In September, the average length of the day is 12h and 31min.On the first day of the month, sunrise is at 6:53 am and sunset at 8:07 pm. On the last day of September, sunrise is at 7:28 am and sunset at 7:12 pm CDT.
Sunshine
The average sunshine in September is 8.8h.UV index
The average daily maximum UV index in September is 4. A UV Index of 3 to 5 symbolizes a moderate health risk from unsafe exposure to UV radiation for the ordinary person.Note: In September, the maximum UV index of 4 suggests these recommendations:
Take measures. Individuals with light skin might experience burns in under 30 minutes. Limiting sun exposure during midday hours helps in reducing the harmful effects of UV radiation. On sunny days, it's ideal to wear sunglasses that filter out UVA and UVB rays.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Bristol, SD
- Average high temperature in September: 71.6°F
The warmest month (with the highest average high temperature) is July (81°F).
The month with the lowest average high temperature is January (18.9°F).
- Average low temperature in September: 51.3°F
The month with the highest average low temperature is July (61.3°F).
The coldest month (with the lowest average low temperature) is January (5°F).
Average pressure in September
Bristol, SD
- Average pressure in September: 29.96"Hg
The month with the highest atmospheric pressure is February (30.17"Hg).
The month with the lowest atmospheric pressure is June (29.85"Hg).
Average wind speed in September
Bristol, SD
- Average wind speed in September: 10.3mph
The windiest month (with the highest average wind speed) is April (11.7mph).
The calmest month (with the lowest average wind speed) is July (8.7mph).
Average humidity in September
Bristol, SD
- Average humidity in September: 66%
The month with the highest relative humidity is January (91%).
The month with the lowest relative humidity is September (66%).
Average rainfall in September
Bristol, SD
- Average rainfall in September: 1.57"
The wettest month (with the highest rainfall) is July (3.58").
The driest month (with the least rainfall) is November (0.63").
Average rainfall days in September
Bristol, SD
- Average rainfall days in September: 10.1 days
The month with the highest number of rainy days is June (17.9 days).
The month with the least rainy days is February (2.3 days).
Average snowfall in September
Bristol, SD
- Average snowfall in September: 0"
The month with the highest snowfall is December (4.53").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in September
Bristol, SD
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (15.1 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Bristol, SD
- Average daylight in September: 12h and 30min
The month with the longest days is June (Average daylight: 15h and 36min).
The month with the shortest days is December (Average daylight: 8h and 48min).
- Average sunshine in September: 8h and 48min
The month with the most sunshine is July (Average sunshine: 10h and 42min).
The month with the least sunshine is January (Average sunshine: 3h and 12min).
Average sunshine days in September
Bristol, SD
- Average sunshine days in September: 18.5 days
The month with the most sunshine days is November (19.5 days).
The month with the least sunshine days is June (10.4 days).
Average UV index in September
Bristol, SD
- Average UV index in September: 4
The months with the highest UV index are June and July (UV index 6).
The months with the lowest UV index are January, November and December (UV index 1).
Average cloud cover in September
Bristol, SD
- Average cloud cover in September: 29
The month with the most cloud cover is January (Cloud cover 66).
The months with the least cloud cover are July and August (Cloud cover 27).
Average visibility in September
Bristol, SD
- Average visibility in September: 6mi
The months with the highest visibility are April, May, June, July, August, September, October and November (6mi).
The months with the lowest visibility are January, February, March and December (5mi).





