September weather forecastChambersburg, PA
September
Weather in September
Seasonal changes become more evident in Chambersburg, Pennsylvania during September. Stressing on the shift, the temperature falls down to 74.3°F (23.5°C) indicating the arrival of fall. As fall begins, the town gets colored in beautiful autumn hues. The pleasant weather combined with the artistic color palette is nothing short of a spectacle. A drop in the UV Index from 5 to 4 marks a significant change in the weather pattern.Temperature
The start of September comes with a small reduction in the average high-temperature, subtly receding from a moderately hot 81.7°F (27.6°C) in August to a still warm 74.3°F (23.5°C). The temperature dips to an average of 55.4°F (13°C) during September nights.Humidity
In Chambersburg, the average relative humidity in September is 79%.Rainfall
In Chambersburg, during September, the rain falls for 13.9 days and regularly aggregates up to 1.89" (48mm) of precipitation. In Chambersburg, Pennsylvania, during the entire year, the rain falls for 156 days and collects up to 27.2" (691mm) of precipitation.Snowfall
June through September are months without snowfall.Daylight
The average length of the day in September is 12h and 26min.On the first day of the month, sunrise is at 6:39 am and sunset at 7:41 pm. On the last day of September, sunrise is at 7:06 am and sunset at 6:54 pm EDT.
Sunshine
In Chambersburg, the average sunshine in September is 8.5h.UV index
In Chambersburg, the average daily maximum UV index in September is 4. A UV Index reading of 3 to 5 represents a medium vulnerability from exposure to the Sun's UV radiation for ordinary individuals.Note: In September, the UV index of 4 transforms into the following advice:
Exercise prevention - Warding off sunburn is urged. Midday is when the Sun's radiation is strongest; avoid prolonged exposure during this time. A hat with a broad brim is indispensable, filtering out up to half of UV rays.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Chambersburg, PA
- Average high temperature in September: 74.3°F
The warmest month (with the highest average high temperature) is July (83.8°F).
The month with the lowest average high temperature is January (35.1°F).
- Average low temperature in September: 55.4°F
The month with the highest average low temperature is July (62.4°F).
The coldest month (with the lowest average low temperature) is January (22.1°F).
Average pressure in September
Chambersburg, 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 (29.95"Hg).
Average wind speed in September
Chambersburg, PA
- Average wind speed in September: 5.1mph
The windiest month (with the highest average wind speed) is January (7.8mph).
The calmest month (with the lowest average wind speed) is August (4.5mph).
Average humidity in September
Chambersburg, PA
- Average humidity in September: 79%
The months with the highest relative humidity are February and October (80%).
The month with the lowest relative humidity is July (75%).
Average rainfall in September
Chambersburg, PA
- Average rainfall in September: 1.89"
The wettest month (with the highest rainfall) is May (2.95").
The driest month (with the least rainfall) is January (1.85").
Average rainfall days in September
Chambersburg, PA
- Average rainfall days in September: 13.9 days
The month with the highest number of rainy days is May (17.3 days).
The month with the least rainy days is January (7.3 days).
Average snowfall in September
Chambersburg, PA
- Average snowfall in September: 0"
The month with the highest snowfall is January (4.92").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in September
Chambersburg, PA
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (8.6 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Chambersburg, 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 30min
The month with the most sunshine is July (Average sunshine: 10h and 18min).
The month with the least sunshine is February (Average sunshine: 4h and 24min).
Average sunshine days in September
Chambersburg, PA
- Average sunshine days in September: 14.3 days
The month with the most sunshine days is November (18.5 days).
The month with the least sunshine days is May (11.6 days).
Average UV index in September
Chambersburg, 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
Chambersburg, PA
- Average cloud cover in September: 40
The months with the most cloud cover are January, February and December (Cloud cover 52).
The month with the least cloud cover is July (Cloud cover 33).
Average visibility in September
Chambersburg, PA
- Average visibility in September: 5mi
The months with the highest visibility are April, June, July, November and December (6mi).
The months with the lowest visibility are January, February, March, May, August, September and October (5mi).
