September weather forecastHarpers Ferry, WV
September
Weather in September
The first month of the autumn, September, is also a moderately hot month in Harpers Ferry, West Virginia, with temperature in the range of an average low of 57.2°F (14°C) and an average high of 76.8°F (24.9°C).Temperature
The arrival of September is marked by a minor reduction in average high-temperature, sliding from a moderately hot 83.8°F (28.8°C) in August to a still warm 76.8°F (24.9°C). During September, an average low-temperature of 57.2°F (14°C) is observed.Humidity
In Harpers Ferry, the average relative humidity in September is 77%.Rainfall
In Harpers Ferry, in September, during 13.8 rainfall days, 2.01" (51mm) of precipitation is typically accumulated. Throughout the year, there are 163.3 rainfall days, and 29.84" (758mm) of precipitation is accumulated.Snowfall
May through October are months without snowfall.Daylight
In Harpers Ferry, the average length of the day in September is 12h and 26min.On the first day of the month, sunrise is at 6:40 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 September, the average sunshine is 9h.UV index
The average daily maximum UV index in September is 4. A UV Index estimate of 3 to 5 represents a medium vulnerability from exposure to the Sun's UV radiation for the average person.Note: A daily maximum UV index of 4 in September translates into the following instructions:
Be cautious. Those with fair skin can be subjected to burns in fewer than 30 minutes. Considering the Sun's intensity during midday, it's wise to minimize direct exposure. Always opt for UVA and UVB-resistant sunglasses on radiant days.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Harpers Ferry, WV
- Average high temperature in September: 76.8°F
The warmest month (with the highest average high temperature) is July (86.4°F).
The month with the lowest average high temperature is January (38.1°F).
- Average low temperature in September: 57.2°F
The month with the highest average low temperature is July (64.9°F).
The coldest month (with the lowest average low temperature) is January (24.3°F).
Average pressure in September
Harpers Ferry, WV
- 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
Harpers Ferry, WV
- Average wind speed in September: 5mph
The windiest month (with the highest average wind speed) is March (7.5mph).
The calmest month (with the lowest average wind speed) is August (4.4mph).
Average humidity in September
Harpers Ferry, WV
- Average humidity in September: 77%
The month with the highest relative humidity is October (79%).
The months with the lowest relative humidity are April and July (74%).
Average rainfall in September
Harpers Ferry, WV
- Average rainfall in September: 2.01"
The wettest month (with the highest rainfall) is May (3.35").
The driest month (with the least rainfall) is January (1.97").
Average rainfall days in September
Harpers Ferry, WV
- Average rainfall days in September: 13.8 days
The month with the highest number of rainy days is May (19.3 days).
The month with the least rainy days is January (9.1 days).
Average snowfall in September
Harpers Ferry, WV
- Average snowfall in September: 0"
The month with the highest snowfall is January (3.62").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in September
Harpers Ferry, WV
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (6.9 days).
The months with the least snowfall days are May, June, July, August, September and October (0 days).
Average daylight in September /
Average sunshine in September
Harpers Ferry, WV
- Average daylight in September: 12h and 24min
The month with the longest days is June (Average daylight: 14h and 54min).
The month with the shortest days is December (Average daylight: 9h and 30min).
- Average sunshine in September: 9h and 0min
The month with the most sunshine is July (Average sunshine: 10h and 42min).
The months with the least sunshine are January and February (Average sunshine: 5h and 0min).
Average sunshine days in September
Harpers Ferry, WV
- Average sunshine days in September: 14.4 days
The month with the most sunshine days is November (18.6 days).
The month with the least sunshine days is May (10.7 days).
Average UV index in September
Harpers Ferry, WV
- 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
Harpers Ferry, WV
- 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 31).
Average visibility in September
Harpers Ferry, WV
- Average visibility in September: 5mi
The months with the highest visibility are February, March, April, June, July, August and November (6mi).
The months with the lowest visibility are January, May, September, October and December (5mi).





