September weather forecastManchester, CT
September
Weather in September
September in Manchester offers an exceptional weather experience, with the city making a smooth transition from summer to fall. The temperatures begin to cool off, making room for the arrival of autumn’s colors. The days become shorter, and the city gets prepared for the autumn season. The change in Manchester's weather is marked by reduced temperatures, averaging to a high of 73.4°F (23°C). End of September witnesses trees shedding leaves, signaling the onset of the fall season.Temperature
The onset of September aligns with a soft reduction in the average high-temperature, gently falling from 81°F (27.2°C) in August to a still moderately hot 73.4°F (23°C). During the month of September, Manchester anticipates a mean low-temperature of 55.2°F (12.9°C).Humidity
In September, the average relative humidity in Manchester is 77%.Rainfall
The month with the least rainfall is September, when the rain falls for 12.5 days and typically collects 1.77" (45mm) of precipitation.Snowfall
June through September are months without snowfall.Daylight
The average length of the day in September is 12h and 28min.On the first day of September, sunrise is at 6:16 am and sunset at 7:23 pm. On the last day of the month, sunrise is at 6:46 am and sunset at 6:33 pm EDT.
Sunshine
In September, the average sunshine is 8.7h.UV index
In September, the average daily maximum UV index is 4. A UV Index estimate of 3 to 5 represents a moderate threat to health from exposure to the Sun's UV radiation for average individuals.Note: The daily maximum UV index of 4 in September interprets into the following advice:
Prioritize safety - Recommendations to avert sunburn are shared. The midday Sun can be dangerous due to its intense radiation; always find shade and reduce exposure. Your best bet for sun defense on the face, eyes, and neck is a hat with a wide brim.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Manchester, CT
- Average high temperature in September: 73.4°F
The warmest month (with the highest average high temperature) is July (83.1°F).
The month with the lowest average high temperature is January (32.9°F).
- Average low temperature in September: 55.2°F
The month with the highest average low temperature is July (63.5°F).
The coldest month (with the lowest average low temperature) is January (21.2°F).
Average pressure in September
Manchester, CT
- Average pressure in September: 30.06"Hg
The month with the highest atmospheric pressure is November (30.09"Hg).
The month with the lowest atmospheric pressure is June (29.93"Hg).
Average wind speed in September
Manchester, CT
- Average wind speed in September: 5.8mph
The windiest months (with the highest average wind speed) are January and March (8.1mph).
The calmest month (with the lowest average wind speed) is August (5.2mph).
Average humidity in September
Manchester, CT
- Average humidity in September: 77%
The month with the highest relative humidity is February (80%).
The month with the lowest relative humidity is April (71%).
Average rainfall in September
Manchester, CT
- Average rainfall in September: 1.77"
The wettest month (with the highest rainfall) is December (3.27").
The driest month (with the least rainfall) is September (1.77").
Average rainfall days in September
Manchester, CT
- Average rainfall days in September: 12.5 days
The month with the highest number of rainy days is July (17.3 days).
The month with the least rainy days is January (10 days).
Average snowfall in September
Manchester, CT
- Average snowfall in September: 0"
The month with the highest snowfall is February (4.8").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in September
Manchester, CT
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is February (8.5 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Manchester, 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 42min
The months with the most sunshine are July and August (Average sunshine: 10h and 24min).
The month with the least sunshine is February (Average sunshine: 4h and 36min).
Average sunshine days in September
Manchester, CT
- Average sunshine days in September: 14.6 days
The month with the most sunshine days is November (17.2 days).
The month with the least sunshine days is June (11.2 days).
Average UV index in September
Manchester, CT
- Average UV index in September: 4
The months with the highest UV index are June and July (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
Manchester, CT
- Average cloud cover in September: 37
The month with the most cloud cover is February (Cloud cover 49).
The month with the least cloud cover is August (Cloud cover 33).
Average visibility in September
Manchester, CT
- Average visibility in September: 5mi
The months with the highest visibility are January, March, April, June, July, August, October, November and December (6mi).
The months with the lowest visibility are February, May and September (5mi).
