September weather forecastCabin John, MD
September
Weather in September
September, the first month of the autumn in Cabin John, is also a moderately hot month, with an average temperature ranging between min 61.5°F (16.4°C) and max 78.4°F (25.8°C).Temperature
The transition to September results in a modest reduction in average high-temperature, moving from a moderately hot 85.8°F (29.9°C) in August to a still warm 78.4°F (25.8°C). An average low-temperature of 61.5°F (16.4°C) is observed during the September nights.Humidity
The average relative humidity in September is 73%.Rainfall
In Cabin John, in September, it is raining for 12.5 days, with typically 2.05" (52mm) of accumulated precipitation. In Cabin John, during the entire year, the rain falls for 150.3 days and collects up to 28.66" (728mm) of precipitation.Snowfall
In Cabin John, 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 6:38 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 Cabin John, the average sunshine in September is 8.8h.UV index
In September, the average daily maximum UV index is 5. A UV Index value of 3 to 5 symbolizes a moderate threat to health from unsafe exposure to UV radiation for the ordinary person.Note: In September, the maximum UV index of 5 transforms into these recommendations:
Act with care - The suggestion to avoid sunburn is emphasized. Midday is when the Sun's radiation is strongest; avoid prolonged exposure during this time. Sunglasses that guard against UVA and UVB rays are pivotal in minimizing sun-induced ocular damage.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Cabin John, MD
- Average high temperature in September: 78.4°F
The warmest month (with the highest average high temperature) is July (87.8°F).
The month with the lowest average high temperature is January (39.9°F).
- Average low temperature in September: 61.5°F
The month with the highest average low temperature is July (69.4°F).
The coldest month (with the lowest average low temperature) is January (27°F).
Average pressure in September
Cabin John, 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
Cabin John, MD
- Average wind speed in September: 5.7mph
The windiest month (with the highest average wind speed) is March (8mph).
The calmest month (with the lowest average wind speed) is August (5.1mph).
Average humidity in September
Cabin John, MD
- Average humidity in September: 73%
The month with the highest relative humidity is December (76%).
The month with the lowest relative humidity is July (69%).
Average rainfall in September
Cabin John, MD
- Average rainfall in September: 2.05"
The wettest month (with the highest rainfall) is August (3.82").
The driest month (with the least rainfall) is January (1.69").
Average rainfall days in September
Cabin John, MD
- Average rainfall days in September: 12.5 days
The month with the highest number of rainy days is May (17.1 days).
The month with the least rainy days is November (8.5 days).
Average snowfall in September
Cabin John, MD
- Average snowfall in September: 0"
The month with the highest snowfall is January (2.6").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in September
Cabin John, MD
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is February (4.4 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
Cabin John, 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 48min
The month with the most sunshine is July (Average sunshine: 10h and 42min).
The months with the least sunshine are January, February and December (Average sunshine: 5h and 0min).
Average sunshine days in September
Cabin John, MD
- Average sunshine days in September: 15.8 days
The month with the most sunshine days is November (20.4 days).
The months with the least sunshine days are May and July (12.3 days).
Average UV index in September
Cabin John, 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
Cabin John, 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
Cabin John, 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).
