September weather forecastAdelphi Park, MD
September
Weather in September
September, the first month of the autumn in Adelphi Park, is also a moderately hot month, with temperature in the range of an average low of 61.7°F (16.5°C) and an average high of 78.4°F (25.8°C).Temperature
Start of September brings a slight shift in the average high-temperature, dipping a bit from August's warm 85.6°F (29.8°C) to a still moderately hot 78.4°F (25.8°C). In the month of September, Adelphi Park records a consistent average low-temperature of 61.7°F (16.5°C).Humidity
In Adelphi Park, the average relative humidity in September is 73%.Rainfall
In September, the rain falls for 12.4 days. Throughout September, 2.2" (56mm) of precipitation is accumulated. Throughout the year, there are 154.8 rainfall days, and 30.28" (769mm) of precipitation is accumulated.Snowfall
In Adelphi Park, snow does not fall in May through October.Daylight
In September, the average length of the day is 12h and 26min.On the first day of September, sunrise is at 6:37 am and sunset at 7:37 pm. On the last day of the month, sunrise is at 7:03 am and sunset at 6:51 pm EDT.
Sunshine
The average sunshine in September is 8.7h.UV index
The average daily maximum UV index in September is 5. A UV Index reading of 3 to 5 represents a medium health hazard from unsafe exposure to UV radiation for ordinary individuals.Note: The maximum UV index of 5 during September translates into these guidelines:
Prioritize safety - Suggestions to prevent sun damage are offered. Considering the strength of solar radiation at midday, one should avoid direct Sun exposure. A wide-brimmed hat provides unparalleled sun protection for sensitive areas like the eyes, ears, and neck.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Adelphi Park, MD
- Average high temperature in September: 78.4°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 (39.7°F).
- Average low temperature in September: 61.7°F
The month with the highest average low temperature is July (69.6°F).
The coldest month (with the lowest average low temperature) is January (27.1°F).
Average pressure in September
Adelphi Park, 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
Adelphi Park, MD
- Average wind speed in September: 5.8mph
The windiest month (with the highest average wind speed) is March (8.1mph).
The calmest month (with the lowest average wind speed) is August (5.2mph).
Average humidity in September
Adelphi Park, MD
- Average humidity in September: 73%
The months with the highest relative humidity are May, October and December (75%).
The month with the lowest relative humidity is July (69%).
Average rainfall in September
Adelphi Park, MD
- Average rainfall in September: 2.2"
The wettest month (with the highest rainfall) is August (3.86").
The driest month (with the least rainfall) is January (1.89").
Average rainfall days in September
Adelphi Park, MD
- Average rainfall days in September: 12.4 days
The month with the highest number of rainy days is May (17.7 days).
The month with the least rainy days is November (8.5 days).
Average snowfall in September
Adelphi Park, MD
- Average snowfall in September: 0"
The month with the highest snowfall is January (2.87").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in September
Adelphi Park, MD
- 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
Adelphi Park, 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 42min
The month with the most sunshine is July (Average sunshine: 10h and 36min).
The month with the least sunshine is February (Average sunshine: 4h and 54min).
Average sunshine days in September
Adelphi Park, MD
- Average sunshine days in September: 16.1 days
The month with the most sunshine days is November (19.5 days).
The month with the least sunshine days is May (12 days).
Average UV index in September
Adelphi Park, 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
Adelphi Park, MD
- 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 32).
Average visibility in September
Adelphi Park, 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).





