September weather forecastBristol, RI
September
Weather in September
As September arrives in Bristol, signs of the impending autumn become increasingly apparent. A significant change is noticeable in the temperature, plunging from summer's sweltering heat to the moderate digits of early fall. September experiences a decrease in sunlight hours as the equinox endorses the beginning of shorter days. Despite this shift, the Bristol weather retains a mild warmth, embracing the oncoming fall with grace and charm. The cityscape gradually welcomes the kaleidoscopic colours of fall, overlaying the departing summer hues.Temperature
September's arrival subtly correlates with a reduction in the average high-temperature, down from a moderately hot 78.6°F (25.9°C) in August to an agreeable 72.1°F (22.3°C). September brings Bristol a consistent average low-temperature of 58.8°F (14.9°C).Humidity
The average relative humidity in September is 78%.Rainfall
September is the month with the least rainfall. Rain falls for 11.2 days and accumulates 1.06" (27mm) of precipitation.Snowfall
In Bristol, snow does not fall in June through October.Daylight
In September, the average length of the day is 12h and 28min.On the first day of September, sunrise is at 6:11 am and sunset at 7:17 pm. On the last day of the month, sunrise is at 6:41 am and sunset at 6:28 pm EDT.
Sunshine
In September, the average sunshine is 8.8h.UV index
The average daily maximum UV index in September is 4. A UV Index reading of 3 to 5 represents a medium vulnerability from exposure to the Sun's UV radiation for ordinary individuals.Note: A maximum high UV index of 4 in September translates into the following recommendations:
Undertake protective steps - Recommendations to avoid sunburn are issued. Sun's radiation is most powerful around mid-day, so it's best to limit outdoor activities during this time. Clothes that are both tight-knit and comfortably loose are prime choices for sun protection.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Bristol, RI
- Average high temperature in September: 72.1°F
The warmest month (with the highest average high temperature) is July (79.3°F).
The month with the lowest average high temperature is January (36°F).
- Average low temperature in September: 58.8°F
The month with the highest average low temperature is July (65.5°F).
The coldest month (with the lowest average low temperature) is January (25.2°F).
Average pressure in September
Bristol, RI
- Average pressure in September: 30.05"Hg
The month with the highest atmospheric pressure is November (30.07"Hg).
The month with the lowest atmospheric pressure is June (29.93"Hg).
Average wind speed in September
Bristol, RI
- Average wind speed in September: 8.2mph
The windiest months (with the highest average wind speed) are January, February and March (10.9mph).
The calmest month (with the lowest average wind speed) is August (7.3mph).
Average humidity in September
Bristol, RI
- Average humidity in September: 78%
The month with the highest relative humidity is June (80%).
The month with the lowest relative humidity is April (73%).
Average rainfall in September
Bristol, RI
- Average rainfall in September: 1.06"
The wettest month (with the highest rainfall) is October (1.97").
The driest month (with the least rainfall) is September (1.06").
Average rainfall days in September
Bristol, RI
- Average rainfall days in September: 11.2 days
The month with the highest number of rainy days is July (15 days).
The month with the least rainy days is February (6.9 days).
Average snowfall in September
Bristol, RI
- Average snowfall in September: 0"
The month with the highest snowfall is March (2.13").
The months with the least snowfall are June, July, August, September and October (0").
Average snowfall days in September
Bristol, RI
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (5.9 days).
The months with the least snowfall days are June, July, August, September and October (0 days).
Average daylight in September /
Average sunshine in September
Bristol, RI
- Average daylight in September: 12h and 30min
The month with the longest days is June (Average daylight: 15h and 12min).
The month with the shortest days is December (Average daylight: 9h and 12min).
- Average sunshine in September: 8h and 48min
The month with the most sunshine is August (Average sunshine: 10h and 36min).
The months with the least sunshine are February and December (Average sunshine: 4h and 54min).
Average sunshine days in September
Bristol, RI
- Average sunshine days in September: 15.9 days
The month with the most sunshine days is November (19.2 days).
The month with the least sunshine days is April (13.6 days).
Average UV index in September
Bristol, RI
- Average UV index in September: 4
The months with the highest UV index are June, July and August (UV index 6).
The months with the lowest UV index are January, February, March and December (UV index 2).
Average cloud cover in September
Bristol, RI
- Average cloud cover in September: 32
The month with the most cloud cover is March (Cloud cover 48).
The month with the least cloud cover is August (Cloud cover 29).
Average visibility in September
Bristol, RI
- Average visibility in September: 6mi
The months with the highest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
The months with the lowest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
