September weather forecast
Riverdale Gardens, MD

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Weather in September

September, the first month of the autumn in Riverdale Gardens, is also a moderately hot month, with temperature in the range of an average low of 62.2°F (16.8°C) and an average high of 78.1°F (25.6°C).

Temperature

September signifies a gentle decline in Riverdale Gardens's average high-temperature, easing from 85.1°F (29.5°C) in August to a still moderately hot 78.1°F (25.6°C). An average low-temperature of 62.2°F (16.8°C) is recorded during the nights in September.

Humidity

In Riverdale Gardens, the average relative humidity in September is 74%.

Rainfall

In Riverdale Gardens, in September, it is raining for 12.3 days, with typically 2.09" (53mm) of accumulated precipitation. Throughout the year, there are 157.9 rainfall days, and 31.14" (791mm) of precipitation is accumulated.

Snowfall

In Riverdale Gardens, snow does not fall in May through November.

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 9.1h.

UV index

In September, the average daily maximum UV index is 5. A UV Index estimate of 3 to 5 represents a medium health hazard from unprotected exposure to Sun's UV rays for the average person.
Note: A maximum high UV index of 5 in September translates into the following recommendations:
Guard yourself - Avoiding sunburn is suggested. The midday Sun can be harmful due to its potent UV radiation; seek shade and reduce exposure. Fend off the sun's harsh rays with appropriate clothing, a wide-brim hat, and UV-protective sunglasses.
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Frequently asked questions

What are the temperatures in Riverdale Gardens in September?

The high-temperature, in September, in Riverdale Gardens, records 78.1°F (25.6°C), while the low-temperature is 62.2°F (16.8°C). The average heat index (a.k.a. 'apparent temperature', 'feels like'), which factors the actual air temperature with the relative humidity, in August is estimated at 93.2°F (34°C).

What is the average humidity in September in Riverdale Gardens?

The average relative humidity in September in Riverdale Gardens is 74%.

How much does it rain in Riverdale Gardens in September?

In Riverdale Gardens, Maryland, in September, it is raining for 12.3 days, with typically 2.09" (53mm) of accumulated precipitation.

When it does not snow in Riverdale Gardens?

May through November are months without snowfall in Riverdale Gardens, Maryland.

What is the average length of the day in September in Riverdale Gardens?

In Riverdale Gardens, the average day length in September is 12h and 26min.

What time are sunrise and sunset in September in Riverdale Gardens?

In September, on the first day of the month, sunrise is at 6:37 am and sunset at 7:37 pm. On the last day of the month, in Riverdale Gardens, Maryland, sunrise is at 7:03 am and sunset at 6:51 pm EDT.

How many hours of sunshine does Riverdale Gardens have in September?

The average sunshine duration in September in Riverdale Gardens, Maryland, is 9.1h.

How high is the UV index in September in Riverdale Gardens?

In Riverdale Gardens, the average daily maximum UV index in September is 5. A UV Index value of 3 to 5 symbolizes a medium health risk from exposure to Sun's UV rays.
Average humidity
Average rainfall days
Average snowfall
Average snowfall days
Average daylight
Average sunshine
Average sunshine days
Average UV index
Average cloud cover
Average visibility

Average temperature in September
Riverdale Gardens, MD

Average temperature in September - Riverdale Gardens, MD
  • Average high temperature in September: 78.1°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 (39.9°F).

  • Average low temperature in September: 62.2°F

The month with the highest average low temperature is July (70°F).
The coldest month (with the lowest average low temperature) is January (27.7°F).

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Average pressure in September
Riverdale Gardens, MD

Average pressure in September - Riverdale Gardens, 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 (29.94"Hg).

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Average wind speed in September
Riverdale Gardens, MD

Average wind speed in September - Riverdale Gardens, MD
  • Average wind speed in September: 6.1mph

The windiest month (with the highest average wind speed) is March (8.3mph).
The calmest month (with the lowest average wind speed) is August (5.3mph).

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Average humidity in September
Riverdale Gardens, MD

Average humidity in September - Riverdale Gardens, MD
  • Average humidity in September: 74%

The months with the highest relative humidity are May, October and December (76%).
The months with the lowest relative humidity are April and July (71%).

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Average rainfall in September
Riverdale Gardens, MD

Average rainfall in September - Riverdale Gardens, MD
  • Average rainfall in September: 2.09"

The wettest month (with the highest rainfall) is August (3.58").
The driest month (with the least rainfall) is January (2.01").

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Average rainfall days in September
Riverdale Gardens, MD

Average rainfall days in September - Riverdale Gardens, MD
  • Average rainfall days in September: 12.3 days

The month with the highest number of rainy days is May (17.9 days).
The month with the least rainy days is November (9 days).

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Average snowfall in September
Riverdale Gardens, MD

Average snowfall in September - Riverdale Gardens, 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, October and November (0").

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Average snowfall days in September
Riverdale Gardens, MD

Average snowfall days in September - Riverdale Gardens, MD
  • Average snowfall days in September: 0 days

The month with the highest number of snowfall days is January (4.1 days).
The months with the least snowfall days are May, June, July, August, September and October (0 days).

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Average daylight in September /
Average sunshine in September
Riverdale Gardens, MD

Average daylight in September / Average sunshine in September - Riverdale Gardens, 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: 9h and 1min

The month with the most sunshine is July (Average sunshine: 10h and 54min).
The month with the least sunshine is February (Average sunshine: 5h and 0min).

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Average sunshine days in September
Riverdale Gardens, MD

Average sunshine days in September - Riverdale Gardens, MD
  • Average sunshine days in September: 15.6 days

The month with the most sunshine days is November (19.1 days).
The month with the least sunshine days is May (11.8 days).

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Average UV index in September
Riverdale Gardens, MD

Average UV index in September - Riverdale Gardens, 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 and December (UV index 2).

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Average cloud cover in September
Riverdale Gardens, MD

Average cloud cover in September - Riverdale Gardens, MD
  • Average cloud cover in September: 36

The month with the most cloud cover is March (Cloud cover 46).
The month with the least cloud cover is July (Cloud cover 29).

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Average visibility in September
Riverdale Gardens, MD

Average visibility in September - Riverdale Gardens, 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).

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Riverdale Gardens, Maryland, USA

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