September weather forecastEast William Penn, PA
September
Weather in September
September, the first month of the autumn in East William Penn, is also an agreeable month, with temperature in the range of an average high of 72.7°F (22.6°C) and an average low of 53.8°F (12.1°C).Temperature
With the arrival of September, East William Penn notices a mild change in the average high-temperature, sliding from August's moderately hot 78.4°F (25.8°C) to an agreeable 72.7°F (22.6°C). Throughout the month of September, East William Penn observes an average nighttime temperature of 53.8°F (12.1°C).Humidity
The average relative humidity in September is 80%.Rainfall
The month with the least rainfall is September, when the rain falls for 12.5 days and typically collects 1.97" (50mm) of precipitation.Snowfall
June through September are months without snowfall.Daylight
In East William Penn, the average length of the day in September is 12h and 27min.On the first day of the month, sunrise is at 6:32 am and sunset at 7:36 pm. On the last day of September, sunrise is at 7:01 am and sunset at 6:48 pm EDT.
Sunshine
The average sunshine in September is 8.8h.UV index
In East William Penn, the average daily maximum UV index in September is 4. A UV Index estimate of 3 to 5 represents a moderate health risk from unsafe exposure to UV radiation for the ordinary person.Note: The maximum daily UV index of 4 in September converts into the following recommendations:
Undertake protective steps - Obligation to safeguard skin and eyes from harm is in place. It's recommended to limit sun exposure when its radiation is at its peak during midday. For optimum UV protection, wear sun-resistant attire complemented with a hat and quality shades.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
East William Penn, PA
- Average high temperature in September: 72.7°F
The warmest month (with the highest average high temperature) is July (81.1°F).
The month with the lowest average high temperature is January (31.8°F).
- Average low temperature in September: 53.8°F
The month with the highest average low temperature is July (61.2°F).
The coldest month (with the lowest average low temperature) is January (19.6°F).
Average pressure in September
East William Penn, PA
- Average pressure in September: 30.07"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
East William Penn, PA
- Average wind speed in September: 5.5mph
The windiest month (with the highest average wind speed) is March (8.3mph).
The calmest month (with the lowest average wind speed) is August (4.8mph).
Average humidity in September
East William Penn, PA
- Average humidity in September: 80%
The month with the highest relative humidity is February (83%).
The month with the lowest relative humidity is April (77%).
Average rainfall in September
East William Penn, PA
- Average rainfall in September: 1.97"
The wettest month (with the highest rainfall) is May (3.39").
The driest month (with the least rainfall) is September (1.97").
Average rainfall days in September
East William Penn, PA
- Average rainfall days in September: 12.5 days
The month with the highest number of rainy days is May (19 days).
The month with the least rainy days is January (9.7 days).
Average snowfall in September
East William Penn, PA
- Average snowfall in September: 0"
The month with the highest snowfall is January (7.24").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in September
East William Penn, PA
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (12.7 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
East William Penn, PA
- Average daylight in September: 12h and 30min
The month with the longest days is June (Average daylight: 15h and 6min).
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 months with the least sunshine are January and February (Average sunshine: 4h and 18min).
Average sunshine days in September
East William Penn, PA
- Average sunshine days in September: 14.9 days
The month with the most sunshine days is November (15.8 days).
The month with the least sunshine days is May (9.1 days).
Average UV index in September
East William Penn, PA
- Average UV index in September: 4
The months with the highest UV index are May, June, July and August (UV index 5).
The months with the lowest UV index are January, February, March, November and December (UV index 2).
Average cloud cover in September
East William Penn, PA
- Average cloud cover in September: 39
The month with the most cloud cover is February (Cloud cover 55).
The month with the least cloud cover is July (Cloud cover 33).
Average visibility in September
East William Penn, PA
- Average visibility in September: 5mi
The month with the highest visibility is April (6mi).
The months with the lowest visibility are January, February, March, May, June, July, August, September, October, November and December (5mi).
