September weather forecastRochester, MA
September
Weather in September
September, the first month of the autumn in Rochester, is still a pleasant month, with an average temperature ranging between min 60.4°F (15.8°C) and max 70°F (21.1°C).Temperature
September witnesses a gentle descent in average high-temperature, descending from August's moderately hot 76.6°F (24.8°C) to an agreeable 70°F (21.1°C). Rochester's average low-temperature in September is measured at a refreshing 60.4°F (15.8°C).Humidity
The average relative humidity in September is 78%.Rainfall
In September, the rain falls for 10.6 days. Throughout September, 1.06" (27mm) of precipitation is accumulated. In Rochester, during the entire year, the rain falls for 136.3 days and collects up to 15.63" (397mm) of precipitation.Snowfall
June through September are months without snowfall.Daylight
In Rochester, Massachusetts, the average length of the day in September is 12h and 28min.On the first day of September, sunrise is at 6:10 am and sunset at 7:16 pm. On the last day of the month, sunrise is at 6:39 am and sunset at 6:26 pm EDT.
Sunshine
In Rochester, the average sunshine in September is 8.7h.UV index
In Rochester, the average daily maximum UV index in September is 4. A UV Index estimate of 3 to 5 represents a moderate health risk from unsafe exposure to UV radiation for average individuals.Note: The maximum UV index, 4 during September, leads to the following recommendations:
Guard yourself - An obligation to protect skin and eyes from harm exists. To prevent harmful UV exposure, minimize direct contact with the Sun around midday. For a sun-safe wardrobe, go for clothes that are tightly woven and generously sized.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Rochester, MA
- Average high temperature in September: 70°F
The warmest month (with the highest average high temperature) is August (76.6°F).
The month with the lowest average high temperature is January (36.7°F).
- Average low temperature in September: 60.4°F
The month with the highest average low temperature is August (66.7°F).
The coldest month (with the lowest average low temperature) is January (27.3°F).
Average pressure in September
Rochester, MA
- Average pressure in September: 30.05"Hg
The month with the highest atmospheric pressure is November (30.06"Hg).
The month with the lowest atmospheric pressure is June (29.93"Hg).
Average wind speed in September
Rochester, MA
- Average wind speed in September: 9.8mph
The windiest month (with the highest average wind speed) is January (12.9mph).
The calmest month (with the lowest average wind speed) is August (8.3mph).
Average humidity in September
Rochester, MA
- Average humidity in September: 78%
The months with the highest relative humidity are June and July (80%).
The months with the lowest relative humidity are March and November (74%).
Average rainfall in September
Rochester, MA
- Average rainfall in September: 1.06"
The wettest month (with the highest rainfall) is October (1.89").
The driest month (with the least rainfall) is February (0.98").
Average rainfall days in September
Rochester, MA
- Average rainfall days in September: 10.6 days
The months with the highest number of rainy days are May and July (14.1 days).
The month with the least rainy days is February (7.7 days).
Average snowfall in September
Rochester, MA
- Average snowfall in September: 0"
The month with the highest snowfall is February (1.1").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in September
Rochester, MA
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (6.6 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Rochester, 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 42min
The month with the most sunshine is August (Average sunshine: 10h and 42min).
The month with the least sunshine is February (Average sunshine: 4h and 48min).
Average sunshine days in September
Rochester, MA
- Average sunshine days in September: 16.6 days
The month with the most sunshine days is December (17.7 days).
The month with the least sunshine days is April (14.3 days).
Average UV index in September
Rochester, 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
Rochester, MA
- Average cloud cover in September: 31
The month with the most cloud cover is March (Cloud cover 49).
The month with the least cloud cover is August (Cloud cover 28).
Average visibility in September
Rochester, 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).





