September weather forecastGrantley, PA
September
Weather in September
September, the first month of the autumn in Grantley, is also a moderately hot month, with temperature in the range of an average high of 75°F (23.9°C) and an average low of 57.2°F (14°C).Temperature
As August shifts into September, a minor alteration in temperatures is observed, with average highs reducing from a moderately hot 81°F (27.2°C) to a still warm 75°F (23.9°C). The temperature in Grantley dips to an average of 57.2°F (14°C) during September nights.Humidity
In Grantley, the average relative humidity in September is 79%.Rainfall
In September, the rain falls for 12.1 days. Throughout September, 1.61" (41mm) of precipitation is accumulated. In Grantley, during the entire year, the rain falls for 139.8 days and collects up to 22.95" (583mm) of precipitation.Snowfall
June through September are months without snowfall in Grantley.Daylight
In Grantley, the average length of the day in September is 12h and 26min.On the first day of the month, sunrise is at 6:35 am and sunset at 7:37 pm. On the last day of September, sunrise is at 7:02 am and sunset at 6:50 pm EDT.
Sunshine
In September, the average sunshine is 8.9h.UV index
The average daily maximum UV index in September is 4. A UV Index value of 3 to 5 symbolizes a moderate threat to health from unsafe exposure to UV radiation for the ordinary person.Note: In September, a daily UV index of 4 turns into the following recommendations:
Exercise prevention - Protecting skin and eyes from harm is required. During midday, the Sun's radiation is strongest, and it's advisable to reduce direct exposure. During bright days, sunglasses that offer UVA and UVB defense are recommended.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Grantley, PA
- Average high temperature in September: 75°F
The warmest month (with the highest average high temperature) is July (83.5°F).
The month with the lowest average high temperature is January (35.8°F).
- Average low temperature in September: 57.2°F
The month with the highest average low temperature is July (65.5°F).
The coldest month (with the lowest average low temperature) is January (23.4°F).
Average pressure in September
Grantley, PA
- Average pressure in September: 30.06"Hg
The month with the highest atmospheric pressure is November (30.14"Hg).
The month with the lowest atmospheric pressure is June (29.94"Hg).
Average wind speed in September
Grantley, PA
- Average wind speed in September: 5.8mph
The windiest month (with the highest average wind speed) is March (8.9mph).
The calmest month (with the lowest average wind speed) is August (5.1mph).
Average humidity in September
Grantley, PA
- Average humidity in September: 79%
The month with the highest relative humidity is May (81%).
The months with the lowest relative humidity are March, April and November (76%).
Average rainfall in September
Grantley, PA
- Average rainfall in September: 1.61"
The wettest month (with the highest rainfall) is August (2.8").
The driest month (with the least rainfall) is February (1.26").
Average rainfall days in September
Grantley, PA
- Average rainfall days in September: 12.1 days
The month with the highest number of rainy days is May (15.9 days).
The month with the least rainy days is January (6.3 days).
Average snowfall in September
Grantley, PA
- Average snowfall in September: 0"
The month with the highest snowfall is March (3.23").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in September
Grantley, PA
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is February (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
Grantley, 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 54min
The month with the most sunshine is July (Average sunshine: 10h and 36min).
The month with the least sunshine is February (Average sunshine: 4h and 42min).
Average sunshine days in September
Grantley, PA
- Average sunshine days in September: 15.7 days
The month with the most sunshine days is January (20.4 days).
The month with the least sunshine days is May (11.7 days).
Average UV index in September
Grantley, PA
- Average UV index in September: 4
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
Grantley, PA
- Average cloud cover in September: 37
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 31).
Average visibility in September
Grantley, 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).





