September weather forecastRiva Trace, MD
September
Weather in September
The first month of the autumn, September, is still a warm month in Riva Trace, Maryland, with temperature in the range of an average high of 77°F (25°C) and an average low of 64.6°F (18.1°C).Temperature
The onset of September entails a subtle temperature shift, as the average high-temperature eases from a warm 83.3°F (28.5°C) in August to a still moderately hot 77°F (25°C). An average low-temperature of 64.6°F (18.1°C) is common during the nights of September.Humidity
In Riva Trace, the average relative humidity in September is 75%.Rainfall
In Riva Trace, in September, during 10.5 rainfall days, 0.63" (16mm) of precipitation is typically accumulated. In Riva Trace, during the entire year, the rain falls for 120.4 days and collects up to 10.47" (266mm) of precipitation.Snowfall
In Riva Trace, snow does not fall in April through October.Daylight
The average length of the day in September is 12h and 26min.On the first day of the month, sunrise is at 6:35 am and sunset at 7:36 pm. On the last day of September, sunrise is at 7:01 am and sunset at 6:50 pm EDT.
Sunshine
In September, the average sunshine is 9.2h.UV index
In Riva Trace, the average daily maximum UV index in September is 5. A UV Index value of 3 to 5 symbolizes a moderate health risk from unprotected exposure to Sun's UV rays for average individuals.Note: In September, a daily maximum UV index of 5 leads to the following instructions:
Exercise care. People with light skin might get burns in fewer than 30 minutes. The best time to avoid the Sun's harmful UV radiation is during midday when it's most potent. For optimum UV protection, wear sun-resistant attire complemented with a hat and quality shades.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Riva Trace, MD
- Average high temperature in September: 77°F
The warmest month (with the highest average high temperature) is July (84.7°F).
The month with the lowest average high temperature is January (40.3°F).
- Average low temperature in September: 64.6°F
The month with the highest average low temperature is July (72°F).
The coldest month (with the lowest average low temperature) is January (29.8°F).
Average pressure in September
Riva Trace, MD
- 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 (29.94"Hg).
Average wind speed in September
Riva Trace, MD
- Average wind speed in September: 7.6mph
The windiest month (with the highest average wind speed) is January (10mph).
The calmest months (with the lowest average wind speed) are July and August (6.6mph).
Average humidity in September
Riva Trace, MD
- Average humidity in September: 75%
The month with the highest relative humidity is May (78%).
The months with the lowest relative humidity are January, March, April and November (72%).
Average rainfall in September
Riva Trace, MD
- Average rainfall in September: 0.63"
The wettest month (with the highest rainfall) is August (1.69").
The driest month (with the least rainfall) is January (0.47").
Average rainfall days in September
Riva Trace, MD
- Average rainfall days in September: 10.5 days
The months with the highest number of rainy days are July and August (14.3 days).
The month with the least rainy days is November (5.3 days).
Average snowfall in September
Riva Trace, MD
- Average snowfall in September: 0"
The month with the highest snowfall is January (0.67").
The months with the least snowfall are April, May, June, July, August, September and October (0").
Average snowfall days in September
Riva Trace, MD
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is February (2.5 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
Riva Trace, 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: 9h and 12min
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
Riva Trace, MD
- Average sunshine days in September: 17.4 days
The month with the most sunshine days is November (23.4 days).
The month with the least sunshine days is August (13.8 days).
Average UV index in September
Riva Trace, 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 and December (UV index 2).
Average cloud cover in September
Riva Trace, MD
- Average cloud cover in September: 33
The months with the most cloud cover are February and March (Cloud cover 45).
The month with the least cloud cover is July (Cloud cover 28).
Average visibility in September
Riva Trace, MD
- Average visibility in September: 6mi
The months with the highest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
The months with the lowest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).





