Contents
- Weather in September
- Frequently asked questions
- Average temperature in September
- Average pressure in September
- Average wind speed in September
- Average humidity in September
- Average rainfall in September
- Average rainfall days in September
- Average snowfall in September
- Average snowfall days in September
- Average daylight in September
- Average sunshine in September
- Average sunshine days in September
- Average UV index in September
- Average cloud cover in September
- Average visibility in September
Weather in September
Temperature
The onset of September introduces a moderate change in Frederick's weather, with average high-temperatures falling from August's warm 81.9°F (27.7°C) to an agreeable 72.7°F (22.6°C). Frederick's average low-temperature in the month of September is recorded at a cool 52.2°F (11.2°C).Humidity
The months with the lowest humidity are August and September, with an average relative humidity of 61%.Rainfall
In Frederick, in September, during 8.4 rainfall days, 1.14" (29mm) of precipitation is typically accumulated. Throughout the year, there are 92.3 rainfall days, and 15.28" (388mm) of precipitation is accumulated.Snowfall
In Frederick, snow does not fall in June through September.Daylight
In Frederick, the average length of the day in September is 12h and 31min.On the first day of September, sunrise is at 6:56 am and sunset at 8:11 pm. On the last day of the month, sunrise is at 7:32 am and sunset at 7:15 pm CDT.
Sunshine
The average sunshine in September is 8.5h.UV index
In Frederick, the average daily maximum UV index in September is 4. A UV Index of 3 to 5 symbolizes a moderate health risk from exposure to the Sun's UV rays for average individuals.Note: The maximum daily UV index, 4 in September, converts into the following recommendations:
Ensure safety - Imperative it is to shield skin and eyes from damage. Minimize direct exposure to the Sun during midday when its radiation is at its peak. Wearing sunglasses with both UVA and UVB protection effectively reduces sun-induced eye damage.
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Data Sources | Weather Forecasting & Climate
Frequently asked questions
What is the average September temperature?
What are the least humid months?
What is the average humidity in September in Frederick?
How many days does it rain in September?
When it does not snow?
Does it snow in September?
How many hours of daylight does Frederick have in September?
What time are sunrise and sunset in September?
How long on average sun shines in September?
What is the UV index reading in September?
Average temperature in September
Frederick, SD
- Average high temperature in September: 72.7°F
The warmest month (with the highest average high temperature) is July (82.9°F).
The month with the lowest average high temperature is January (19.8°F).
- Average low temperature in September: 52.2°F
The month with the highest average low temperature is July (61.7°F).
The coldest month (with the lowest average low temperature) is January (5.4°F).
Average pressure in September
Frederick, SD
- Average pressure in September: 29.96"Hg
The month with the highest atmospheric pressure is February (30.17"Hg).
The month with the lowest atmospheric pressure is June (29.85"Hg).
Average wind speed in September
Frederick, SD
- Average wind speed in September: 9.6mph
The windiest months (with the highest average wind speed) are April and October (10.7mph).
The calmest month (with the lowest average wind speed) is August (8.2mph).
Average humidity in September
Frederick, SD
- Average humidity in September: 61%
The month with the highest relative humidity is January (89%).
The months with the lowest relative humidity are August and September (61%).
Average rainfall in September
Frederick, SD
- Average rainfall in September: 1.14"
The wettest month (with the highest rainfall) is June (2.83").
The driest month (with the least rainfall) is January (0.39").
Average rainfall days in September
Frederick, SD
- Average rainfall days in September: 8.4 days
The month with the highest number of rainy days is June (14.3 days).
The month with the least rainy days is January (1.7 days).
Average snowfall in September
Frederick, SD
- Average snowfall in September: 0"
The months with the highest snowfall are January and December (2.76").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in September
Frederick, SD
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is February (11.8 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Frederick, SD
- Average daylight in September: 12h and 3min
The month with the longest days is June (Average daylight: 15h and 42min).
The month with the shortest days is December (Average daylight: 8h and 42min).
- Average sunshine in September: 8h and 3min
The month with the most sunshine is July (Average sunshine: 11h and 0min).
The month with the least sunshine is January (Average sunshine: 3h and 48min).
Average sunshine days in September
Frederick, SD
- Average sunshine days in September: 20.4 days
The month with the most sunshine days is November (21.5 days).
The month with the least sunshine days is June (13.8 days).
Average UV index in September
Frederick, SD
- Average UV index in September: 4
The months with the highest UV index are June and July (UV index 6).
The months with the lowest UV index are January, November and December (UV index 1).
Average cloud cover in September
Frederick, SD
- Average cloud cover in September: 27
The month with the most cloud cover is January (Cloud cover 59).
The month with the least cloud cover is August (Cloud cover 24).
Average visibility in September
Frederick, SD
- Average visibility in September: 6mi
The months with the highest visibility are February, April, May, June, July, August, September, October, November and December (6mi).
The months with the lowest visibility are January and March (5mi).
Frederick, South Dakota, USA
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