Contents
- Weather in September
- Frequently asked questions
- Average temperature in September
- Average pressure in September
- Average wind speed in September
- Average humidity in September
- Average rainfall in September
- Average rainfall days in September
- Average snowfall in September
- Average snowfall days in September
- Average daylight in September
- Average sunshine in September
- Average sunshine days in September
- Average UV index in September
- Average cloud cover in September
- Average visibility in September
Weather in September
Temperature
In September, the average high-temperature marginally drops from a warm 85.6°F (29.8°C) in August to a still moderately hot 78.4°F (25.8°C). In September, in Reston, the average low-temperature is 60.8°F (16°C).Humidity
The average relative humidity in September is 74%.Rainfall
In Reston, it is raining for 12.5 days, with typically 1.93" (49mm) of accumulated precipitation. In Reston, Virginia, during the entire year, the rain falls for 152.8 days and collects up to 27.64" (702mm) of precipitation.Snowfall
In Reston, snow does not fall in May through October.Daylight
In September, the average length of the day in Reston, Virginia, is 12h and 26min.On the first day of the month, sunrise is at 6:38 am and sunset at 7:40 pm. On the last day of September, in Reston, sunrise is at 7:04 am and sunset at 6:54 pm EDT.
Sunshine
The average sunshine in September in Reston is 8.7h.UV index
The average daily maximum UV index in September is 5. A UV Index estimate of 3 to 5 represents a medium health hazard from unprotected exposure to Sun's UV rays for the ordinary person.Note: The daily maximum UV index of 5 in September interpret into the following advice:
Take precautions - Protection against skin and eye damage is obliged. The Sun's most intense and consequently most harmful UV radiation during midday hours should be decreased by minimizing exposure and seeking shade. A wide-brim hat offers excellent sun protection for the eyes, ears, face, and neck. Sunglasses with UVA and UVB protection significantly reduce eye damage from sun exposure. Tightly woven, loose-fitting clothes provide additional protection from the Sun.
FAQ
What is the temperature in September in Reston?
What is the average humidity in September in Reston?
How many days does it rain in September in Reston?
When it does not snow in Reston?
What is the average length of the day in September in Reston?
When are sunrise and sunset in September in Reston?
How long on average sun shines in September in Reston?
What is the UV index reading in September in Reston?
Average temperature in September
Reston, VA
- Average high temperature in September: 78.4°F
The warmest month (with the highest average high temperature) is July (87.6°F).
The month with the lowest average high temperature is January (39.7°F).
- Average low temperature in September: 60.8°F
The month with the highest average low temperature is July (68.5°F).
The coldest month (with the lowest average low temperature) is January (26.4°F).
Average pressure in September
Reston, VA
- Average pressure in September: 30.05"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
Reston, VA
- Average wind speed in September: 5.5mph
The windiest month (with the highest average wind speed) is March (7.7mph).
The calmest month (with the lowest average wind speed) is August (4.9mph).
Average humidity in September
Reston, VA
- Average humidity in September: 74%
The months with the highest relative humidity are October and December (76%).
The month with the lowest relative humidity is July (69%).
Average rainfall in September
Reston, VA
- Average rainfall in September: 1.93"
The wettest month (with the highest rainfall) is August (3.39").
The driest month (with the least rainfall) is January (1.77").
Average rainfall days in September
Reston, VA
- Average rainfall days in September: 12.5 days
The month with the highest number of rainy days is May (16.3 days).
The month with the least rainy days is November (9.3 days).
Average snowfall in September
Reston, VA
- Average snowfall in September: 0"
The month with the highest snowfall is January (2.28").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in September
Reston, VA
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (4.6 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
Reston, VA
- Average daylight in September: 12h and 2min
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: 8h and 4min
The month with the most sunshine is July (Average sunshine: 10h and 42min).
The months with the least sunshine are January, February and December (Average sunshine: 5h and 0min).
Average sunshine days in September
Reston, VA
- Average sunshine days in September: 16.3 days
The month with the most sunshine days is November (19.3 days).
The month with the least sunshine days is May (12.8 days).
Average UV index in September
Reston, VA
- Average UV index in September: 5
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
Reston, VA
- Average cloud cover in September: 38
The month with the most cloud cover is March (Cloud cover 47).
The month with the least cloud cover is July (Cloud cover 31).
Average visibility in September
Reston, VA
- 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).
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