September weather forecastChatham, PA
September
Weather in September
September, the first month of the autumn in Chatham, is also a moderately hot month, with an average temperature fluctuating between 75°F (23.9°C) and 58.8°F (14.9°C).Temperature
September signifies a minor drop in average high-temperature, transitioning from 81.9°F (27.7°C) in August to a still moderately hot 75°F (23.9°C). An average temperature of 58.8°F (14.9°C) is recorded during the nights in September.Humidity
February, May, September, October and December, with an average relative humidity of 79%, are the most humid months in Chatham.Rainfall
The months with the least rainfall are January, September and November Rain falls for 10.8 days and accumulates 0.87" (22mm) of rain.Snowfall
June through October are months without snowfall.Daylight
In Chatham, the average length of the day in September is 12h and 26min.On the first day of September, sunrise is at 6:31 am and sunset at 7:34 pm. On the last day of the month, sunrise is at 6:59 am and sunset at 6:46 pm EDT.
Sunshine
In September, the average sunshine is 8.9h.UV index
In September, the average daily maximum UV index in Chatham is 4. A UV Index estimate of 3 to 5 represents a moderate health risk from unprotected exposure to Sun's UV rays for the average person.Note: In September, a regular UV index of 4 translates into these guidelines:
Undertake precautions - Guarding against sun damage is counselled. To prevent harmful UV exposure, minimize direct contact with the Sun around midday. Clothes that are both tight-knit and comfortably loose are prime choices for sun protection.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Chatham, PA
- Average high temperature in September: 75°F
The warmest month (with the highest average high temperature) is July (84.2°F).
The month with the lowest average high temperature is January (36.9°F).
- Average low temperature in September: 58.8°F
The month with the highest average low temperature is July (66.6°F).
The coldest month (with the lowest average low temperature) is January (24.6°F).
Average pressure in September
Chatham, PA
- Average pressure in September: 30.06"Hg
The month with the highest atmospheric pressure is November (30.13"Hg).
The month with the lowest atmospheric pressure is June (29.94"Hg).
Average wind speed in September
Chatham, PA
- Average wind speed in September: 5.8mph
The windiest months (with the highest average wind speed) are February and March (8.8mph).
The calmest month (with the lowest average wind speed) is August (5.2mph).
Average humidity in September
Chatham, PA
- Average humidity in September: 79%
The months with the highest relative humidity are February, May, September, October and December (79%).
The months with the lowest relative humidity are March and April (75%).
Average rainfall in September
Chatham, PA
- Average rainfall in September: 0.87"
The wettest month (with the highest rainfall) is August (1.93").
The driest months (with the least rainfall) are January, September and November (0.87").
Average rainfall days in September
Chatham, PA
- Average rainfall days in September: 10.8 days
The month with the highest number of rainy days is July (14.9 days).
The month with the least rainy days is January (5.9 days).
Average snowfall in September
Chatham, PA
- Average snowfall in September: 0"
The month with the highest snowfall is March (1.26").
The months with the least snowfall are June, July, August, September and October (0").
Average snowfall days in September
Chatham, PA
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (5.1 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Chatham, 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 42min).
The month with the least sunshine is February (Average sunshine: 4h and 48min).
Average sunshine days in September
Chatham, PA
- Average sunshine days in September: 17.6 days
The month with the most sunshine days is November (21.5 days).
The month with the least sunshine days is July (12.9 days).
Average UV index in September
Chatham, 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
Chatham, PA
- Average cloud cover in September: 37
The months with the most cloud cover are February and March (Cloud cover 47).
The month with the least cloud cover is July (Cloud cover 30).
Average visibility in September
Chatham, PA
- Average visibility in September: 6mi
The months with the highest visibility are January, February, March, April, June, July, August, September, October, November and December (6mi).
The month with the lowest visibility is May (5mi).
