September weather forecastDurham, NH
September
Weather in September
September ushers in the early signs of fall in Durham. Compared to August, the temperatures in September show a decline but remain comfortably warm. The month of September marks a substantial decrease in rainfall, measuring at 1.46" (37mm). As fall approaches, the days shorten and temperatures drop, preparing Durham for the oncoming cooler months. Regardless, lingering warmth from the summer offers an opportunity to enjoy the stunning fall foliage.Temperature
September ushers in a minor alteration in Durham's climate, with the average high-temperature moving from August's warm 76.8°F (24.9°C) to a pleasant 69.6°F (20.9°C). Durham reports an average nighttime low-temperature of 55°F (12.8°C) in September.Humidity
In September, the average relative humidity is 79%.Rainfall
The month with the least rainfall in Durham is September, when the rain falls for 11.4 days and typically collects 1.46" (37mm) of precipitation.Snowfall
May through September are months without snowfall.Daylight
In September, the average length of the day is 12h and 29min.On the first day of September, sunrise is at 6:08 am and sunset at 7:18 pm. On the last day of the month, sunrise is at 6:40 am and sunset at 6:26 pm EDT.
Sunshine
In Durham, the average sunshine in September is 8.5h.UV index
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 radiation for the average person.Note: A maximum daily UV index of 4 during September morphs into the following directions:
Take heed. Individuals of lighter complexion can be burned in less than half an hour. It's crucial to reduce time in the direct Sun around mid-day due to the intense solar radiation. Employ a hat with a wide brim for robust protection, cutting UV exposure by half.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Durham, NH
- Average high temperature in September: 69.6°F
The warmest month (with the highest average high temperature) is July (77.4°F).
The month with the lowest average high temperature is January (31.5°F).
- Average low temperature in September: 55°F
The month with the highest average low temperature is July (61.5°F).
The coldest month (with the lowest average low temperature) is January (19.8°F).
Average pressure in September
Durham, NH
- Average pressure in September: 30.05"Hg
The month with the highest atmospheric pressure is November (30.06"Hg).
The month with the lowest atmospheric pressure is June (29.92"Hg).
Average wind speed in September
Durham, NH
- Average wind speed in September: 7mph
The windiest month (with the highest average wind speed) is January (10.8mph).
The calmest months (with the lowest average wind speed) are July and August (6.2mph).
Average humidity in September
Durham, NH
- Average humidity in September: 79%
The months with the highest relative humidity are January and February (80%).
The months with the lowest relative humidity are April and November (75%).
Average rainfall in September
Durham, NH
- Average rainfall in September: 1.46"
The wettest months (with the highest rainfall) are October and December (2.87").
The driest month (with the least rainfall) is September (1.46").
Average rainfall days in September
Durham, NH
- Average rainfall days in September: 11.4 days
The month with the highest number of rainy days is May (15 days).
The month with the least rainy days is February (7.6 days).
Average snowfall in September
Durham, NH
- Average snowfall in September: 0"
The month with the highest snowfall is December (4.53").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in September
Durham, NH
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (8.7 days).
The months with the least snowfall days are May, June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Durham, NH
- Average daylight in September: 12h and 30min
The month with the longest days is June (Average daylight: 15h and 18min).
The month with the shortest days is December (Average daylight: 9h and 6min).
- Average sunshine in September: 8h and 30min
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 48min).
Average sunshine days in September
Durham, NH
- Average sunshine days in September: 16.5 days
The month with the most sunshine days is November (17.1 days).
The month with the least sunshine days is April (13.2 days).
Average UV index in September
Durham, NH
- Average UV index in September: 4
The months with the highest UV index are 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
Durham, NH
- Average cloud cover in September: 33
The month with the most cloud cover is March (Cloud cover 50).
The month with the least cloud cover is August (Cloud cover 30).
Average visibility in September
Durham, NH
- 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).
