September weather forecastHeidelberg, PA
September
Weather in September
September, the first month of the autumn in Heidelberg, is still a warm month, with an average temperature ranging between min 55.8°F (13.2°C) and max 75.7°F (24.3°C).Temperature
September signals a slight drop in average high-temperature, sliding from August's 82.4°F (28°C) to a still moderately hot 75.7°F (24.3°C). During the month of September, an average temperature of 55.8°F (13.2°C) is noted during the nights.Humidity
In September, the average relative humidity is 77%.Rainfall
In Heidelberg, in September, during 10.6 rainfall days, 0.79" (20mm) of precipitation is typically accumulated. Throughout the year, there are 132.6 rainfall days, and 11.5" (292mm) of precipitation is accumulated.Snowfall
In Heidelberg, snow does not fall in May through October.Daylight
In September, the average length of the day is 12h and 27min.On the first day of the month, sunrise is at 6:48 am and sunset at 7:51 pm. On the last day of September, sunrise is at 7:16 am and sunset at 7:03 pm EDT.
Sunshine
The average sunshine in September is 8.5h.UV index
In September, the average daily maximum UV index is 4. A UV Index estimate of 3 to 5 represents a medium health hazard from exposure to the Sun's UV rays for average individuals.Note: A daily high UV index of 4 in September leads to these guidelines:
Adopt protective measures - Requirement to safeguard skin and eyes from harm exists. The most potent solar radiation is around mid-day, so one should minimize exposure to direct sunlight during this period. To mitigate harm from sun exposure, pick sunglasses offering UVA and UVB defense.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Heidelberg, PA
- Average high temperature in September: 75.7°F
The warmest month (with the highest average high temperature) is July (83.7°F).
The month with the lowest average high temperature is January (33.4°F).
- Average low temperature in September: 55.8°F
The month with the highest average low temperature is July (62.2°F).
The coldest month (with the lowest average low temperature) is January (21°F).
Average pressure in September
Heidelberg, PA
- Average pressure in September: 30.05"Hg
The month with the highest atmospheric pressure is November (30.13"Hg).
The month with the lowest atmospheric pressure is June (29.95"Hg).
Average wind speed in September
Heidelberg, PA
- Average wind speed in September: 5.1mph
The windiest month (with the highest average wind speed) is January (7.9mph).
The calmest months (with the lowest average wind speed) are July and August (4.7mph).
Average humidity in September
Heidelberg, PA
- Average humidity in September: 77%
The month with the highest relative humidity is February (85%).
The months with the lowest relative humidity are July and August (75%).
Average rainfall in September
Heidelberg, PA
- Average rainfall in September: 0.79"
The wettest month (with the highest rainfall) is July (1.34").
The driest month (with the least rainfall) is November (0.67").
Average rainfall days in September
Heidelberg, PA
- Average rainfall days in September: 10.6 days
The month with the highest number of rainy days is July (15.6 days).
The month with the least rainy days is February (6.4 days).
Average snowfall in September
Heidelberg, PA
- Average snowfall in September: 0"
The month with the highest snowfall is February (0.98").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in September
Heidelberg, PA
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (9.3 days).
The months with the least snowfall days are May, June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Heidelberg, 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 18min).
- Average sunshine in September: 8h and 30min
The month with the most sunshine is August (Average sunshine: 10h and 12min).
The month with the least sunshine is January (Average sunshine: 3h and 0min).
Average sunshine days in September
Heidelberg, PA
- Average sunshine days in September: 16.4 days
The month with the most sunshine days is November (19.6 days).
The month with the least sunshine days is May (12.2 days).
Average UV index in September
Heidelberg, PA
- Average UV index in September: 4
The months with the highest UV index are June, July and August (UV index 6).
The month with the lowest UV index is December (UV index 1).
Average cloud cover in September
Heidelberg, PA
- Average cloud cover in September: 38
The month with the most cloud cover is January (Cloud cover 68).
The month with the least cloud cover is August (Cloud cover 33).
Average visibility in September
Heidelberg, PA
- Average visibility in September: 5mi
The months with the highest visibility are April, June, July, August and November (6mi).
The months with the lowest visibility are January, February, March, May, September, October and December (5mi).





