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
As August makes way for September, Jefferson's average high-temperature eases from a warm 82°F (27.8°C) to a still moderately hot 76.1°F (24.5°C). September's nights in Jefferson observe an average temperature of 55°F (12.8°C).Humidity
The average relative humidity in September in Jefferson is 70%.Rainfall
In September, the rain falls for 11.8 days. Throughout September, 1.93" (49mm) of precipitation is accumulated. In Jefferson, South Dakota, during the entire year, the rain falls for 122 days and collects up to 21.61" (549mm) of precipitation.Snowfall
In Jefferson, snow does not fall in June through September.Daylight
In September, the average length of the day in Jefferson is 12h and 28min.On the first day of September in Jefferson, sunrise is at 6:52 am and sunset at 7:59 pm. On the last day of the month, sunrise is at 7:23 am and sunset at 7:08 pm CDT.
Sunshine
In September, the average sunshine is 8.8h.UV index
In Jefferson, South Dakota, the average daily maximum UV index in September 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: The daily high UV index of 5 in September translates into this advice:
Exercise prevention - Precautions against solar damage are endorsed. Direct exposure to the Sun during its peak hours around mid-day should be minimized for safety. Opt for tightly woven and loose clothing to enhance protection from the Sun.
Frequently asked questions
What are September temperatures in Jefferson?
What is the average humidity in September in Jefferson?
How much does it rain in Jefferson in September?
When it does not snow in Jefferson?
Does it snow in Jefferson in September?
What is the average length of the day in September in Jefferson?
When are sunrise and sunset in September in Jefferson?
How many hours of sunshine does Jefferson have in September?
How high is the UV index in September in Jefferson?
Average temperature in September
Jefferson, SD
- Average high temperature in September: 76.1°F
The warmest month (with the highest average high temperature) is July (84°F).
The month with the lowest average high temperature is January (27°F).
- Average low temperature in September: 55°F
The month with the highest average low temperature is July (64.9°F).
The coldest month (with the lowest average low temperature) is January (13.1°F).
Average pressure in September
Jefferson, SD
- Average pressure in September: 29.98"Hg
The month with the highest atmospheric pressure is January (30.16"Hg).
The month with the lowest atmospheric pressure is June (29.86"Hg).
Average wind speed in September
Jefferson, SD
- Average wind speed in September: 9mph
The windiest month (with the highest average wind speed) is April (11.1mph).
The calmest month (with the lowest average wind speed) is July (7.6mph).
Average humidity in September
Jefferson, SD
- Average humidity in September: 70%
The month with the highest relative humidity is January (84%).
The month with the lowest relative humidity is October (65%).
Average rainfall in September
Jefferson, SD
- Average rainfall in September: 1.93"
The wettest months (with the highest rainfall) are May and June (3.03").
The driest month (with the least rainfall) is February (0.67").
Average rainfall days in September
Jefferson, SD
- Average rainfall days in September: 11.8 days
The month with the highest number of rainy days is June (17.8 days).
The month with the least rainy days is February (3.3 days).
Average snowfall in September
Jefferson, SD
- Average snowfall in September: 0"
The month with the highest snowfall is January (2.95").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in September
Jefferson, SD
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (9.6 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Jefferson, SD
- Average daylight in September: 12h and 3min
The month with the longest days is June (Average daylight: 15h and 18min).
The month with the shortest days is December (Average daylight: 9h and 6min).
- Average sunshine in September: 8h and 5min
The month with the most sunshine is July (Average sunshine: 10h and 42min).
The month with the least sunshine is January (Average sunshine: 4h and 24min).
Average sunshine days in September
Jefferson, SD
- Average sunshine days in September: 16.4 days
The month with the most sunshine days is November (20.9 days).
The month with the least sunshine days is June (9.7 days).
Average UV index in September
Jefferson, SD
- Average UV index in September: 5
The months with the highest UV index are June and July (UV index 6).
The month with the lowest UV index is January (UV index 1).
Average cloud cover in September
Jefferson, SD
- Average cloud cover in September: 28
The month with the most cloud cover is January (Cloud cover 52).
The month with the least cloud cover is July (Cloud cover 26).
Average visibility in September
Jefferson, SD
- 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).
Jefferson, South Dakota, USA
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