September weather forecastMarlborough, CT
September
Weather in September
September, the first month of the autumn in Marlborough, is also a moderately hot month, with temperature in the range of an average high of 73.4°F (23°C) and an average low of 56.7°F (13.7°C).Temperature
The shift from August to September includes a minor decrease in the average high-temperature, lightly dropping from 80.2°F (26.8°C) to a still moderately hot 73.4°F (23°C). Marlborough anticipates an average minimum temperature of 56.7°F (13.7°C) in the month of September.Humidity
The average relative humidity in September in Marlborough is 78%.Rainfall
September is the month with the least rainfall. Rain falls for 7.5 days and accumulates 0.35" (9mm) of precipitation.Snowfall
In Marlborough, 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 6:16 am and sunset at 7:22 pm. On the last day of the month, sunrise is at 6:46 am and sunset at 6:32 pm EDT.
Sunshine
In Marlborough, Connecticut, the average sunshine in September is 8.4h.UV index
In Marlborough, the average daily maximum UV index in September is 4. A UV Index estimate of 3 to 5 represents a medium health hazard from exposure to the Sun's UV rays for average individuals.Note: In September, the maximum UV index of 4 suggests this advice:
Put precautions into practice - Ensuring skin and eye safety is a necessity. The solar radiation is most powerful near the mid-day, so the exposure to the direct Sun should be reduced accordingly. For effective sun eye protection, rely on sunglasses certified for UVA and UVB resistance.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Marlborough, CT
- Average high temperature in September: 73.4°F
The warmest month (with the highest average high temperature) is July (82.2°F).
The month with the lowest average high temperature is January (34.3°F).
- Average low temperature in September: 56.7°F
The month with the highest average low temperature is July (64°F).
The coldest month (with the lowest average low temperature) is January (22.8°F).
Average pressure in September
Marlborough, CT
- Average pressure in September: 30.05"Hg
The month with the highest atmospheric pressure is November (30.08"Hg).
The month with the lowest atmospheric pressure is June (29.93"Hg).
Average wind speed in September
Marlborough, CT
- Average wind speed in September: 6.2mph
The windiest months (with the highest average wind speed) are January and March (8.6mph).
The calmest month (with the lowest average wind speed) is August (5.6mph).
Average humidity in September
Marlborough, CT
- Average humidity in September: 78%
The month with the highest relative humidity is February (79%).
The month with the lowest relative humidity is April (71%).
Average rainfall in September
Marlborough, CT
- Average rainfall in September: 0.35"
The wettest month (with the highest rainfall) is December (1.02").
The driest month (with the least rainfall) is September (0.35").
Average rainfall days in September
Marlborough, CT
- Average rainfall days in September: 7.5 days
The month with the highest number of rainy days is July (11.8 days).
The month with the least rainy days is January (5.1 days).
Average snowfall in September
Marlborough, CT
- Average snowfall in September: 0"
The month with the highest snowfall is March (1.26").
The months with the least snowfall are June, July, August, September and October (0").
Average snowfall days in September
Marlborough, CT
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is February (6.4 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
Marlborough, CT
- Average daylight in September: 12h and 30min
The month with the longest days is June (Average daylight: 15h and 6min).
The month with the shortest days is December (Average daylight: 9h and 12min).
- Average sunshine in September: 8h and 24min
The month with the most sunshine is August (Average sunshine: 10h and 18min).
The months with the least sunshine are February and December (Average sunshine: 4h and 36min).
Average sunshine days in September
Marlborough, CT
- Average sunshine days in September: 20.5 days
The month with the most sunshine days is January (21.8 days).
The month with the least sunshine days is July (17.1 days).
Average UV index in September
Marlborough, CT
- Average UV index in September: 4
The months with the highest UV index are June, July and August (UV index 6).
The month with the lowest UV index is December (UV index 1).
Average cloud cover in September
Marlborough, CT
- Average cloud cover in September: 38
The months with the most cloud cover are February and March (Cloud cover 50).
The month with the least cloud cover is August (Cloud cover 34).
Average visibility in September
Marlborough, CT
- Average visibility in September: 6mi
The months with the highest visibility are January, March, April, September, October, November and December (6mi).
The months with the lowest visibility are February, May, June, July and August (5mi).





