September weather forecastOlney, MD
September
Weather in September
September, the first month of the autumn in Olney, is also a moderately hot month, with an average temperature fluctuating between 78.1°F (25.6°C) and 60.8°F (16°C).Temperature
The start of September involves a subtle temperature drop, shifting from a warm 84.9°F (29.4°C) in August to a still moderately hot 78.1°F (25.6°C). The month of September records an average low-temperature of 60.8°F (16°C).Humidity
The average relative humidity in September is 74%.Rainfall
In Olney, Maryland, in September, it is raining for 12.5 days, with typically 2.24" (57mm) of accumulated precipitation. Throughout the year, there are 160.9 rainfall days, and 32.99" (838mm) of precipitation is accumulated.Snowfall
May through October are months without snowfall.Daylight
In Olney, the average length of the day in September is 12h and 26min.On the first day of September in Olney, sunrise is at 6:37 am and sunset at 7:38 pm. On the last day of the month, sunrise is at 7:04 am and sunset at 6:52 pm EDT.
Sunshine
In September, the average sunshine is 8.9h.UV index
In Olney, Maryland, the average daily maximum UV index in September is 5. A UV Index estimate of 3 to 5 represents a moderate health risk from exposure to the Sun's UV radiation for the ordinary person.Note: A typical high UV index of 5 in September suggests the following recommendations:
Heed the precautions - Suggestions to avoid sunburn are made. The Sun's most harmful UV rays are emitted around midday; avoid staying outdoors for long during this time. Sunglasses that ward off UVA and UVB rays play a pivotal role in reducing solar eye damage.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Olney, MD
- Average high temperature in September: 78.1°F
The warmest month (with the highest average high temperature) is July (87.3°F).
The month with the lowest average high temperature is January (39°F).
- Average low temperature in September: 60.8°F
The month with the highest average low temperature is July (68.7°F).
The coldest month (with the lowest average low temperature) is January (26.2°F).
Average pressure in September
Olney, MD
- 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
Olney, MD
- Average wind speed in September: 5.7mph
The windiest month (with the highest average wind speed) is March (8.1mph).
The calmest month (with the lowest average wind speed) is August (5.1mph).
Average humidity in September
Olney, MD
- Average humidity in September: 74%
The months with the highest relative humidity are May, October and December (76%).
The month with the lowest relative humidity is July (70%).
Average rainfall in September
Olney, MD
- Average rainfall in September: 2.24"
The wettest month (with the highest rainfall) is August (4.13").
The driest month (with the least rainfall) is January (2.17").
Average rainfall days in September
Olney, MD
- Average rainfall days in September: 12.5 days
The month with the highest number of rainy days is May (17.8 days).
The month with the least rainy days is November (8.8 days).
Average snowfall in September
Olney, MD
- Average snowfall in September: 0"
The months with the highest snowfall are January and March (3.03").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in September
Olney, MD
- Average snowfall days in September: 0 days
The months with the highest number of snowfall days are January and February (5.1 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
Olney, MD
- 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: 8h and 54min
The month with the most sunshine is July (Average sunshine: 10h and 48min).
The month with the least sunshine is February (Average sunshine: 5h and 0min).
Average sunshine days in September
Olney, MD
- Average sunshine days in September: 15.6 days
The month with the most sunshine days is November (19.4 days).
The months with the least sunshine days are May and July (11 days).
Average UV index in September
Olney, MD
- 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, November and December (UV index 2).
Average cloud cover in September
Olney, MD
- Average cloud cover in September: 37
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
Olney, MD
- 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).
