September weather forecastThornton, PA
September
Weather in September
September, the first month of the autumn in Thornton, is still a warm month, with an average temperature fluctuating between 60.1°F (15.6°C) and 76.3°F (24.6°C).Temperature
September is characterized by a mild reduction in the average high-temperature, from a warm 83.1°F (28.4°C) in August to a still moderately hot 76.3°F (24.6°C). Thornton temperatures generally rest at a low of 60.1°F (15.6°C) during the September nights.Humidity
In Thornton, the average relative humidity in September is 76%.Rainfall
In Thornton, in September, it is raining for 13.6 days, with typically 2.44" (62mm) of accumulated precipitation. Throughout the year, there are 166.6 rainfall days, and 35.59" (904mm) of precipitation is accumulated.Snowfall
In Thornton, snow does not fall in June through September.Daylight
In September, the average length of the day in Thornton is 12h and 26min.On the first day of the month, sunrise is at 6:30 am and sunset at 7:32 pm. On the last day of September, sunrise is at 6:57 am and sunset at 6:45 pm EDT.
Sunshine
The average sunshine in September is 8.7h.UV index
The average daily maximum UV index in September is 5. A UV Index estimate of 3 to 5 represents a moderate threat to health from exposure to the Sun's UV rays for average individuals.Note: In September, the maximum UV index of 5 transforms into these recommendations:
Be vigilant - Preventing sunburn is recommended. To protect against the Sun's most potent rays, avoid direct exposure around midday. Sun protection is enhanced with clothing that boasts a tight weave yet offers a loose fit.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Thornton, PA
- Average high temperature in September: 76.3°F
The warmest month (with the highest average high temperature) is July (85.6°F).
The month with the lowest average high temperature is January (37°F).
- Average low temperature in September: 60.1°F
The month with the highest average low temperature is July (68.5°F).
The coldest month (with the lowest average low temperature) is January (25.3°F).
Average pressure in September
Thornton, PA
- Average pressure in September: 30.05"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
Thornton, PA
- Average wind speed in September: 5.8mph
The windiest months (with the highest average wind speed) are January and March (8.5mph).
The calmest month (with the lowest average wind speed) is August (5.4mph).
Average humidity in September
Thornton, PA
- Average humidity in September: 76%
The months with the highest relative humidity are February and October (78%).
The month with the lowest relative humidity is April (72%).
Average rainfall in September
Thornton, PA
- Average rainfall in September: 2.44"
The wettest month (with the highest rainfall) is August (4.09").
The driest month (with the least rainfall) is January (2.36").
Average rainfall days in September
Thornton, PA
- Average rainfall days in September: 13.6 days
The month with the highest number of rainy days is May (18.5 days).
The month with the least rainy days is January (8.6 days).
Average snowfall in September
Thornton, PA
- Average snowfall in September: 0"
The month with the highest snowfall is February (3.19").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in September
Thornton, PA
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (6.9 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Thornton, PA
- Average daylight in September: 12h and 24min
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 24min).
- Average sunshine in September: 8h and 42min
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 48min).
Average sunshine days in September
Thornton, PA
- Average sunshine days in September: 14.1 days
The month with the most sunshine days is November (18.4 days).
The month with the least sunshine days is July (10 days).
Average UV index in September
Thornton, PA
- Average UV index in September: 5
The months with the highest UV index are May, June, July and August (UV index 6).
The months with the lowest UV index are January, February, November and December (UV index 2).
Average cloud cover in September
Thornton, PA
- Average cloud cover in September: 39
The months with the most cloud cover are February and March (Cloud cover 48).
The month with the least cloud cover is July (Cloud cover 32).
Average visibility in September
Thornton, PA
- Average visibility in September: 5mi
The months with the highest visibility are January, February, March, April, June, July, August, October, November and December (6mi).
The months with the lowest visibility are May and September (5mi).





