September weather forecastPutnam, CT
September
Weather in September
September, the first month of the autumn in Putnam, is still a pleasant month, with an average temperature varying between 55.4°F (13°C) and 72.3°F (22.4°C).Temperature
The commencement of September includes a gentle temperature shift, with the average high-temperature dropping a bit from a warm 79.7°F (26.5°C) in August to an agreeable 72.3°F (22.4°C). Putnam reports an average low-temperature of 55.4°F (13°C) during the nights of September.Humidity
February, June, July, September and October, with an average relative humidity of 79%, are the most humid months.Rainfall
September is the month with the least rainfall. Rain falls for 13.6 days and accumulates 1.81" (46mm) of precipitation.Snowfall
In Putnam, snow does not fall in June through October.Daylight
In Putnam, Connecticut, the average length of the day in September is 12h and 28min.On the first day of the month, sunrise is at 6:13 am and sunset at 7:20 pm. On the last day of September, in Putnam, sunrise is at 6:44 am and sunset at 6:30 pm EDT.
Sunshine
The average sunshine in September in Putnam is 8.4h.UV index
In September, the average daily maximum UV index is 4. A UV Index value of 3 to 5 symbolizes a medium health hazard from exposure to the Sun's UV rays for average individuals.Note: The average daily UV index of 4 in September transforms into the following instructions:
Be vigilant - A duty to shield skin and eyes from injury exists. UV radiation from the Sun is most dangerous during midday; take precautions and seek shade. 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
Putnam, CT
- Average high temperature in September: 72.3°F
The warmest month (with the highest average high temperature) is July (81.1°F).
The month with the lowest average high temperature is January (33.4°F).
- Average low temperature in September: 55.4°F
The month with the highest average low temperature is July (63.1°F).
The coldest month (with the lowest average low temperature) is January (21.6°F).
Average pressure in September
Putnam, CT
- Average pressure in September: 30.06"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
Putnam, CT
- Average wind speed in September: 6.5mph
The windiest month (with the highest average wind speed) is January (9.3mph).
The calmest month (with the lowest average wind speed) is August (5.9mph).
Average humidity in September
Putnam, CT
- Average humidity in September: 79%
The months with the highest relative humidity are February, June, July, September and October (79%).
The month with the lowest relative humidity is April (73%).
Average rainfall in September
Putnam, CT
- Average rainfall in September: 1.81"
The wettest month (with the highest rainfall) is December (3.43").
The driest month (with the least rainfall) is September (1.81").
Average rainfall days in September
Putnam, CT
- Average rainfall days in September: 13.6 days
The month with the highest number of rainy days is July (17.5 days).
The month with the least rainy days is January (8.3 days).
Average snowfall in September
Putnam, CT
- Average snowfall in September: 0"
The month with the highest snowfall is March (3.7").
The months with the least snowfall are June, July, August, September and October (0").
Average snowfall days in September
Putnam, CT
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (7.8 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
Putnam, CT
- 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 24min
The months with the most sunshine are July and August (Average sunshine: 10h and 12min).
The month with the least sunshine is February (Average sunshine: 4h and 42min).
Average sunshine days in September
Putnam, CT
- Average sunshine days in September: 14.6 days
The month with the most sunshine days is November (17.5 days).
The month with the least sunshine days is June (10.6 days).
Average UV index in September
Putnam, CT
- 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
Putnam, CT
- Average cloud cover in September: 38
The months with the most cloud cover are February and March (Cloud cover 49).
The month with the least cloud cover is August (Cloud cover 34).
Average visibility in September
Putnam, CT
- Average visibility in September: 5mi
The months with the highest visibility are January, February, March, April, October, November and December (6mi).
The months with the lowest visibility are May, June, July, August and September (5mi).





