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
September's onset introduces a mild reduction in the average high-temperature, from a moderately hot 85.5°F (29.7°C) in August to a still warm 78.3°F (25.7°C). North Potomac experiences an average low-temperature of 60.8°F (16°C) in the month of September.Humidity
The average relative humidity in September is 74%.Rainfall
In North Potomac, in September, it is raining for 14.1 days, with typically 2.13" (54mm) of accumulated precipitation. In North Potomac, during the entire year, the rain falls for 156.5 days and collects up to 30.71" (780mm) of precipitation.Snowfall
May through October are months without snowfall.Daylight
In September, the average length of the day is 12h and 26min.On the first day of the month, sunrise is at 6:38 am and sunset at 7:39 pm. On the last day of September, in North Potomac, sunrise is at 7:04 am and sunset at 6:52 pm EDT.
Sunshine
The average sunshine in September is 8.9h.UV index
In North Potomac, the average daily maximum UV index in September is 5. A UV Index reading of 3 to 5 represents a medium health hazard from exposure to the Sun's UV radiation for the average person.Note: The average daily UV index of 5 in September transforms into the following instructions:
Preventative actions are necessary - Suggestions to safeguard against sun damage are in order. To guard against the harmful effects of the Sun, minimize exposure during midday. For excellent sun protection for the eyes, ears, face, and neck, consider a wide-brim hat.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What are the temperatures in North Potomac in September?
What is the average humidity in September?
How much does it rain in September?
When it does not snow?
What is the average length of the day in September?
What time are sunrise and sunset in September?
How long on average sun shines in September?
How high is the UV index in September?
Average temperature in September
North Potomac, MD
- Average high temperature in September: 78.3°F
The warmest month (with the highest average high temperature) is July (87.4°F).
The month with the lowest average high temperature is January (39.4°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
North Potomac, 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
North Potomac, MD
- Average wind speed in September: 5.5mph
The windiest month (with the highest average wind speed) is March (7.8mph).
The calmest month (with the lowest average wind speed) is August (4.9mph).
Average humidity in September
North Potomac, MD
- 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
North Potomac, MD
- Average rainfall in September: 2.13"
The wettest month (with the highest rainfall) is August (3.86").
The driest month (with the least rainfall) is February (1.93").
Average rainfall days in September
North Potomac, MD
- Average rainfall days in September: 14.1 days
The month with the highest number of rainy days is August (17.3 days).
The month with the least rainy days is January (8.1 days).
Average snowfall in September
North Potomac, MD
- Average snowfall in September: 0"
The month with the highest snowfall is March (3.03").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in September
North Potomac, MD
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is February (4.8 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
North Potomac, MD
- 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 5min
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
North Potomac, MD
- Average sunshine days in September: 14.5 days
The month with the most sunshine days is November (19.9 days).
The month with the least sunshine days is May (11.7 days).
Average UV index in September
North Potomac, 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, February, November and December (UV index 2).
Average cloud cover in September
North Potomac, 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
North Potomac, 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).
North Potomac, Maryland, USA
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