September weather forecastStamford, CT
September
Weather in September
With summer drawing a close, September marks the beginning of the fall season in Stamford. Witnessing a decline in temperatures, the shift is apparent from the 80.4°F (26.9°C) recorded in August. September paves the way for cooler, more balanced weather conditions. The rainfall also sees a reduction, making walking tours around the city more enjoyable. While anticipating the approaching autumn, September's weather tends to sway between warm and cool.Temperature
As September begins in Stamford, there is a minor decrease in the average high-temperature, softly falling from a warm 80.4°F (26.9°C) in August to a pleasant 73.2°F (22.9°C). Stamford experiences a steady low-temperature of 61.9°F (16.6°C) throughout September.Humidity
In Stamford, the average relative humidity in September is 74%.Rainfall
In Stamford, in September, during 13.5 rainfall days, 2.76" (70mm) of precipitation is typically accumulated. In Stamford, during the entire year, the rain falls for 164.1 days and collects up to 37.95" (964mm) of precipitation.Snowfall
May through October are months without snowfall.Ocean temperature
In Stamford, in September, the average water temperature is 68.9°F (20.5°C).Note: Swimming is not a pleasant activity for most individuals in 68.9°F (20.5°C). Breathing becomes increasingly challenging to control as the water temperature dips from 69.8°F (21°C) to 59°F (15°C).
Daylight
The average length of the day in September is 12h and 28min.On the first day of September, sunrise is at 6:21 am and sunset at 7:26 pm. On the last day of the month, sunrise is at 6:50 am and sunset at 6:37 pm EDT.
Sunshine
In September, the average sunshine is 8.8h.UV index
In September, the average daily maximum UV index is 4. A UV Index of 3 to 5 symbolizes a moderate health risk from unprotected exposure to Sun's UV rays for the average person.Note: In September, the maximum UV index of 4 suggests this advice:
Adopt protective measures - It is advised to guard against sun damage. Avoiding direct sunlight during midday hours helps reduce the risk from intense UV radiation. For holistic sun protection encompassing the eyes, ears, face, and neck, a wide-brim hat is key.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Stamford, CT
- Average high temperature in September: 73.2°F
The warmest month (with the highest average high temperature) is July (81.3°F).
The month with the lowest average high temperature is January (36°F).
- Average low temperature in September: 61.9°F
The month with the highest average low temperature is July (69.1°F).
The coldest month (with the lowest average low temperature) is January (26.6°F).
Average pressure in September
Stamford, CT
- Average pressure in September: 30.05"Hg
The month with the highest atmospheric pressure is November (30.1"Hg).
The month with the lowest atmospheric pressure is June (29.93"Hg).
Average wind speed in September
Stamford, CT
- Average wind speed in September: 7.6mph
The windiest month (with the highest average wind speed) is January (10.1mph).
The calmest month (with the lowest average wind speed) is July (6.6mph).
Average humidity in September
Stamford, CT
- Average humidity in September: 74%
The months with the highest relative humidity are February, May, June and December (75%).
The months with the lowest relative humidity are April, August and November (72%).
Average rainfall in September
Stamford, CT
- Average rainfall in September: 2.76"
The wettest month (with the highest rainfall) is July (4.25").
The driest months (with the least rainfall) are January and February (2.36").
Average rainfall days in September
Stamford, CT
- Average rainfall days in September: 13.5 days
The month with the highest number of rainy days is July (17.7 days).
The month with the least rainy days is January (8.3 days).
Average snowfall in September
Stamford, CT
- Average snowfall in September: 0"
The months with the highest snowfall are February and March (2.44").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in September
Stamford, 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 May, June, July, August and September (0 days).
Average sea temperature in September
Stamford, CT
- Average sea temperature in September: 68.9°F
The best month for swimming (with the highest average sea temperature) is August (73.1°F).
The coldest month (with the lowest average sea temperature) is February (39.5°F).
Average daylight in September /
Average sunshine in September
Stamford, 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 18min).
- Average sunshine in September: 8h and 48min
The month with the most sunshine is July (Average sunshine: 10h and 30min).
The month with the least sunshine is February (Average sunshine: 4h and 42min).
Average sunshine days in September
Stamford, CT
- Average sunshine days in September: 14.5 days
The month with the most sunshine days is January (17.8 days).
The month with the least sunshine days is June (10.7 days).
Average UV index in September
Stamford, 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
Stamford, CT
- Average cloud cover in September: 35
The month with the most cloud cover is December (Cloud cover 49).
The month with the least cloud cover is August (Cloud cover 31).
Average visibility in September
Stamford, 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).
