September weather forecastNorthampton, PA
September
Weather in September
The first month of the autumn, September, is still a warm month in Northampton, Pennsylvania, with an average temperature fluctuating between 74.1°F (23.4°C) and 55°F (12.8°C).Temperature
The beginning of September brings a minor change in the average high-temperature, shifting from 81°F (27.2°C) in August to a still warm 74.1°F (23.4°C). September nights observe an average temperature dip to a cool 55°F (12.8°C).Humidity
The average relative humidity in September is 79%.Rainfall
September is the month with the least rainfall. Rain falls for 11.6 days and accumulates 1.93" (49mm) of precipitation.Snowfall
June through September are months without snowfall.Daylight
In September, the average length of the day is 12h and 27min.On the first day of the month, sunrise is at 6:29 am and sunset at 7:33 pm. On the last day of September, sunrise is at 6:58 am and sunset at 6:45 pm EDT.
Sunshine
In Northampton, the average sunshine in September is 8.8h.UV index
In Northampton, the average daily maximum UV index in September is 4. A UV Index value of 3 to 5 symbolizes a moderate health risk from exposure to the Sun's UV rays for the ordinary person.Note: In September, an average UV index of 4 transforms into the following instructions:
Take necessary precautions - Defending against sun damage is advocated. To protect against the Sun's most potent rays, avoid direct exposure around midday. Sunglasses that guard against UVA and UVB rays are pivotal in minimizing sun-induced ocular damage.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Northampton, PA
- Average high temperature in September: 74.1°F
The warmest month (with the highest average high temperature) is July (83.3°F).
The month with the lowest average high temperature is January (33.8°F).
- Average low temperature in September: 55°F
The month with the highest average low temperature is July (63.3°F).
The coldest month (with the lowest average low temperature) is January (21.6°F).
Average pressure in September
Northampton, PA
- Average pressure in September: 30.06"Hg
The month with the highest atmospheric pressure is November (30.12"Hg).
The month with the lowest atmospheric pressure is June (29.94"Hg).
Average wind speed in September
Northampton, PA
- Average wind speed in September: 5.5mph
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 (5mph).
Average humidity in September
Northampton, PA
- Average humidity in September: 79%
The month with the highest relative humidity is February (81%).
The months with the lowest relative humidity are April and July (76%).
Average rainfall in September
Northampton, PA
- Average rainfall in September: 1.93"
The wettest month (with the highest rainfall) is July (3.19").
The driest month (with the least rainfall) is September (1.93").
Average rainfall days in September
Northampton, PA
- Average rainfall days in September: 11.6 days
The month with the highest number of rainy days is May (17.2 days).
The month with the least rainy days is January (9.9 days).
Average snowfall in September
Northampton, PA
- Average snowfall in September: 0"
The month with the highest snowfall is March (4.88").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in September
Northampton, PA
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is February (9.7 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Northampton, PA
- Average daylight in September: 12h and 30min
The month with the longest days is June (Average daylight: 15h and 0min).
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 24min).
The month with the least sunshine is February (Average sunshine: 4h and 30min).
Average sunshine days in September
Northampton, PA
- Average sunshine days in September: 15.7 days
The month with the most sunshine days is November (17.3 days).
The month with the least sunshine days is February (11.7 days).
Average UV index in September
Northampton, PA
- 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
Northampton, PA
- Average cloud cover in September: 39
The month with the most cloud cover is February (Cloud cover 52).
The month with the least cloud cover is July (Cloud cover 33).
Average visibility in September
Northampton, PA
- Average visibility in September: 5mi
The months with the highest visibility are April and November (6mi).
The months with the lowest visibility are January, February, March, May, June, July, August, September, October and December (5mi).





