September weather forecastNew London, CT
September
Weather in September
September in New London, Connecticut is characterized by the subtle commencement of fall. A decline in temperature and daylight hours signals the arrival of the harvest season. The average temperature fluctuates between 59.9°F (15.5°C) to 72°F (22.2°C) without any recorded snowfall. Hints of autumn colors start to appear, giving the city a serene beauty. With persistent mild weather conditions, September is an excellent month for outdoor activities and exploration.Temperature
New London's weather subtly changes with the onset of September, barely falling from a warm 77.7°F (25.4°C) in August to a pleasant 72°F (22.2°C). New London witnesses an average low-temperature of 59.9°F (15.5°C) throughout the month of September.Humidity
In New London, Connecticut, the average relative humidity in September is 78%.Rainfall
September is the month with the least rainfall in New London. Rain falls for 12 days and accumulates 1.65" (42mm) of precipitation.Snowfall
In New London, snow does not fall in May through October.Ocean temperature
In September, the average ocean temperature is 68.2°F (20.1°C).Note: Swimming in water of 68.2°F (20.1°C) is not enjoyable for the majority of individuals. Breathing control becomes increasingly challenging as the temperature dips from 69.8°F (21°C) to 59°F (15°C).
Daylight
In September, the average length of the day is 12h and 28min.On the first day of September in New London, sunrise is at 6:15 am and sunset at 7:20 pm. On the last day of the month, sunrise is at 6:44 am and sunset at 6:31 pm EDT.
Sunshine
The average sunshine in September is 8.9h.UV index
The average daily maximum UV index in September in New London is 4. A UV Index reading of 3 to 5 represents a moderate threat to health from exposure to the Sun's UV rays for the average person.Note: A maximum daily UV index of 4 during September morphs into the following directions:
Take measures. Individuals with light skin might experience burns in under 30 minutes. Avoiding the Sun's peak radiation during midday hours is essential for health and safety. On sunny days, it's ideal to wear sunglasses that filter out UVA and UVB rays.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
New London, CT
- Average high temperature in September: 72°F
The warmest month (with the highest average high temperature) is July (78.6°F).
The month with the lowest average high temperature is January (36.1°F).
- Average low temperature in September: 59.9°F
The month with the highest average low temperature is July (66.7°F).
The coldest month (with the lowest average low temperature) is January (26.2°F).
Average pressure in September
New London, 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
New London, CT
- Average wind speed in September: 8.8mph
The windiest month (with the highest average wind speed) is January (11.9mph).
The calmest months (with the lowest average wind speed) are July and August (7.8mph).
Average humidity in September
New London, CT
- Average humidity in September: 78%
The month with the highest relative humidity is June (80%).
The months with the lowest relative humidity are January, March, April and November (74%).
Average rainfall in September
New London, CT
- Average rainfall in September: 1.65"
The wettest month (with the highest rainfall) is December (3.86").
The driest month (with the least rainfall) is September (1.65").
Average rainfall days in September
New London, CT
- Average rainfall days in September: 12 days
The month with the highest number of rainy days is July (15.8 days).
The month with the least rainy days is February (9.5 days).
Average snowfall in September
New London, CT
- Average snowfall in September: 0"
The month with the highest snowfall is March (2.56").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in September
New London, CT
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is February (6.8 days).
The months with the least snowfall days are June, July, August, September and October (0 days).
Average sea temperature in September
New London, CT
- Average sea temperature in September: 68.2°F
The best month for swimming (with the highest average sea temperature) is August (72.1°F).
The coldest month (with the lowest average sea temperature) is February (38.8°F).
Average daylight in September /
Average sunshine in September
New London, 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 54min
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
New London, CT
- Average sunshine days in September: 15.8 days
The month with the most sunshine days is November (16.5 days).
The month with the least sunshine days is February (12.5 days).
Average UV index in September
New London, 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
New London, CT
- Average cloud cover in September: 33
The months with the most cloud cover are February, March and December (Cloud cover 47).
The month with the least cloud cover is August (Cloud cover 29).
Average visibility in September
New London, CT
- 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).
