September weather forecastSwansea, MA
September
Weather in September
The first month of the autumn, September, is also an agreeable month in Swansea, Massachusetts, with an average temperature ranging between max 72.1°F (22.3°C) and min 58.8°F (14.9°C).Temperature
September heralds a minor drop in average high-temperature, sliding from August's moderately hot 78.6°F (25.9°C) to an agreeable 72.1°F (22.3°C). In September, Swansea experiences a temperature dip to an average of 58.8°F (14.9°C) at night.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 Swansea, snow does not fall in June through October.Daylight
In Swansea, the average length of the day in September is 12h and 28min.On the first day of the month, sunrise is at 6:11 am and sunset at 7:17 pm. On the last day of September, sunrise is at 6:41 am and sunset at 6:27 pm EDT.
Sunshine
The average sunshine in September is 8.8h.UV index
The average daily maximum UV index in September in Swansea, Massachusetts, is 4. A UV Index reading of 3 to 5 represents a moderate health risk from exposure to the Sun's UV radiation for ordinary individuals.Note: In September, the maximum UV index of 4 transforms into these recommendations:
Be vigilant - Suggestions to stave off sun damage are provided. To prevent harmful UV exposure, minimize direct contact with the Sun around midday. Consider a wide-brim hat essential for effective sun defense covering your face, neck, and eyes.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Swansea, MA
- 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
Swansea, MA
- 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
Swansea, MA
- 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
Swansea, MA
- 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
Swansea, MA
- 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
Swansea, MA
- 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
Swansea, MA
- 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
Swansea, MA
- 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
Swansea, MA
- 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
Swansea, MA
- 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
Swansea, MA
- 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
Swansea, MA
- 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
Swansea, MA
- 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).





