September weather forecastWellesley Hills, MA
September
Weather in September
The first month of the autumn, September, is also an agreeable month in Wellesley Hills, Massachusetts, with temperature in the range of an average low of 56.3°F (13.5°C) and an average high of 73°F (22.8°C).Temperature
The beginning of September brings a slight decrease in the average high-temperature, transitioning from a moderately hot 81°F (27.2°C) in August to a pleasant 73°F (22.8°C). Wellesley Hills witnesses a consistent average low-temperature of 56.3°F (13.5°C) throughout September.Humidity
In Wellesley Hills, Massachusetts, the average relative humidity in September is 76%.Rainfall
September is the month with the least rainfall. Rain falls for 6.6 days and accumulates 0.24" (6mm) of precipitation.Snowfall
In Wellesley Hills, snow does not fall in June through October.Daylight
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 7:18 pm. On the last day of September, sunrise is at 6:41 am and sunset at 6:27 pm EDT.
Sunshine
In September, the average sunshine is 8.6h.UV index
In September, the average daily maximum UV index is 4. A UV Index estimate of 3 to 5 represents a medium health hazard from exposure to the Sun's UV rays for the average person.Note: The daily high UV index of 4 during September translates into the following recommendations:
Be careful. Light complexion individuals might get burns in fewer than 30 minutes. Minimize direct exposure to the Sun during midday when its radiation is at its peak. A wide-brimmed hat is a shield, deflecting up to 50% of harmful UV radiation from eyes.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Wellesley Hills, MA
- Average high temperature in September: 73°F
The warmest month (with the highest average high temperature) is July (81.9°F).
The month with the lowest average high temperature is January (33.6°F).
- Average low temperature in September: 56.3°F
The month with the highest average low temperature is July (64°F).
The coldest month (with the lowest average low temperature) is January (21.7°F).
Average pressure in September
Wellesley Hills, 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 (29.92"Hg).
Average wind speed in September
Wellesley Hills, MA
- Average wind speed in September: 6.3mph
The windiest month (with the highest average wind speed) is January (9.1mph).
The calmest month (with the lowest average wind speed) is August (5.8mph).
Average humidity in September
Wellesley Hills, MA
- Average humidity in September: 76%
The month with the highest relative humidity is February (78%).
The month with the lowest relative humidity is April (70%).
Average rainfall in September
Wellesley Hills, MA
- Average rainfall in September: 0.24"
The wettest month (with the highest rainfall) is November (0.67").
The driest month (with the least rainfall) is September (0.24").
Average rainfall days in September
Wellesley Hills, MA
- Average rainfall days in September: 6.6 days
The month with the highest number of rainy days is July (10.2 days).
The month with the least rainy days is February (4.1 days).
Average snowfall in September
Wellesley Hills, MA
- Average snowfall in September: 0"
The month with the highest snowfall is December (0.91").
The months with the least snowfall are June, July, August, September and October (0").
Average snowfall days in September
Wellesley Hills, MA
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (4.9 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Wellesley Hills, 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 6min).
- Average sunshine in September: 8h and 36min
The month with the most sunshine is August (Average sunshine: 10h and 30min).
The month with the least sunshine is February (Average sunshine: 4h and 42min).
Average sunshine days in September
Wellesley Hills, MA
- Average sunshine days in September: 21.4 days
The months with the most sunshine days are January and November (22.5 days).
The month with the least sunshine days is June (17.5 days).
Average UV index in September
Wellesley Hills, 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, November and December (UV index 2).
Average cloud cover in September
Wellesley Hills, MA
- Average cloud cover in September: 36
The month with the most cloud cover is March (Cloud cover 50).
The month with the least cloud cover is August (Cloud cover 32).
Average visibility in September
Wellesley Hills, 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).





