September weather forecastPatapsco, MD
September
Weather in September
September, the first month of the autumn in Patapsco, is also a moderately hot month, with temperature in the range of an average low of 57°F (13.9°C) and an average high of 75°F (23.9°C).Temperature
The arrival of September corresponds with a minor reduction in the average high-temperature, down from August's 81.7°F (27.6°C) to a still moderately hot 75°F (23.9°C). Nightly temperatures drop to an average low of 57°F (13.9°C) in September.Humidity
In September, the average relative humidity is 79%.Rainfall
In Patapsco, during September, the rain falls for 13.8 days and regularly aggregates up to 2.44" (62mm) of precipitation. In Patapsco, during the entire year, the rain falls for 158.9 days and collects up to 32.68" (830mm) of precipitation.Snowfall
May through September are months without snowfall.Daylight
In Patapsco, the average length of the day in September is 12h and 26min.On the first day of September, sunrise is at 6:36 am and sunset at 7:38 pm. On the last day of the month, sunrise is at 7:03 am and sunset at 6:51 pm EDT.
Sunshine
In Patapsco, the average sunshine in September is 8.7h.UV index
The average daily maximum UV index in September is 4. A UV Index of 3 to 5 symbolizes a medium vulnerability from unprotected exposure to Sun's UV rays for average individuals.Note: In September, the average maximum UV index of 4 translates into the following recommendations:
Adopt protective measures - It is advised to guard against sun damage. UV radiation from the Sun is most dangerous during midday; take precautions and seek shade. Boost your sun resistance with garments that are densely woven yet spacious.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Patapsco, MD
- Average high temperature in September: 75°F
The warmest month (with the highest average high temperature) is July (83.8°F).
The month with the lowest average high temperature is January (36.9°F).
- Average low temperature in September: 57°F
The month with the highest average low temperature is July (65.7°F).
The coldest month (with the lowest average low temperature) is January (23.9°F).
Average pressure in September
Patapsco, MD
- 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 (29.94"Hg).
Average wind speed in September
Patapsco, MD
- Average wind speed in September: 5.9mph
The windiest months (with the highest average wind speed) are February and March (8.8mph).
The calmest month (with the lowest average wind speed) is August (5.2mph).
Average humidity in September
Patapsco, MD
- Average humidity in September: 79%
The month with the highest relative humidity is May (81%).
The months with the lowest relative humidity are January, April, July and November (76%).
Average rainfall in September
Patapsco, MD
- Average rainfall in September: 2.44"
The wettest month (with the highest rainfall) is August (3.9").
The driest month (with the least rainfall) is February (2.13").
Average rainfall days in September
Patapsco, MD
- Average rainfall days in September: 13.8 days
The month with the highest number of rainy days is May (17.5 days).
The month with the least rainy days is January (8.4 days).
Average snowfall in September
Patapsco, MD
- Average snowfall in September: 0"
The month with the highest snowfall is March (4.06").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in September
Patapsco, MD
- 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 and September (0 days).
Average daylight in September /
Average sunshine in September
Patapsco, 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 24min).
- Average sunshine in September: 8h and 42min
The month with the most sunshine is July (Average sunshine: 10h and 24min).
The months with the least sunshine are January and February (Average sunshine: 4h and 36min).
Average sunshine days in September
Patapsco, MD
- Average sunshine days in September: 14.8 days
The month with the most sunshine days is November (18.6 days).
The month with the least sunshine days is July (11.6 days).
Average UV index in September
Patapsco, MD
- 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
Patapsco, MD
- Average cloud cover in September: 39
The months with the most cloud cover are February and March (Cloud cover 49).
The month with the least cloud cover is July (Cloud cover 32).
Average visibility in September
Patapsco, MD
- Average visibility in September: 5mi
The months with the highest visibility are January, February, March, April, June, July, August, October, November and December (6mi).
The months with the lowest visibility are May and September (5mi).





