September weather forecast
Summit, SD

Share

Weather in September

The first month of the autumn, September, is still a pleasant month in Summit, South Dakota, with an average temperature varying between 72.5°F (22.5°C) and 52.7°F (11.5°C).

Temperature

Summit in September undergoes a slight reduction in the average high-temperature, shifting from August's warm 80.8°F (27.1°C) to a pleasant 72.5°F (22.5°C). September witnesses an average low-temperature hovering around a cool 52.7°F (11.5°C).

Humidity

The average relative humidity in September is 67%.

Rainfall

In Summit, during September, the rain falls for 10 days and regularly aggregates up to 1.61" (41mm) of precipitation. Throughout the year, there are 115.2 rainfall days, and 19.88" (505mm) of precipitation is accumulated.

Snowfall

In Summit, snow does not fall in June through September.

Daylight

The average length of the day in September in Summit is 12h and 31min.
On the first day of September, sunrise is at 6:50 am and sunset at 8:05 pm. On the last day of the month, sunrise is at 7:26 am and sunset at 7:09 pm CDT.

Sunshine

In Summit, the average sunshine in September is 9h.

UV index

In Summit, the average daily maximum UV index in September is 4. A UV Index of 3 to 5 symbolizes a medium health hazard from unsafe exposure to UV radiation for the average person.
Note: The maximum daily UV index of 4 in September converts into the following recommendations:
Take precautions - Protection against sun damage is advised. Minimize direct exposure to the Sun during midday when its radiation is at its peak. Limit sun-induced ocular harm with sunglasses that feature UVA and UVB filtration.
Updated: Aug 31, 2024
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate

Frequently asked questions

What are the temperatures in September?

The average high-temperature and low-temperature in Summit during September are 72.5°F (22.5°C) and 52.7°F (11.5°C) respectively. The average heat index (a.k.a. 'real feel', 'felt air temperature'), which combines air temperature and relative humidity, in August is calculated to be 84.2°F (29°C).

What is the average humidity in September?

In Summit, the average relative humidity in September is 67%.

How much does it rain in September?

In Summit, in September, during 10 rainfall days, 1.61" (41mm) of precipitation is typically accumulated.

When it does not snow?

In Summit, South Dakota, snow does not fall in June through September.

Does it snow in September?

In Summit, in September, it doesn't snow. In October, it regularly snows.

What is the average length of the day in September?

In September, the average day length is 12h and 31min.

When is the sunrise / sunset in September?

In September, on the first day of the month, sunrise is at 6:50 am and sunset at 8:05 pm. On the last day of the month, sunrise is at 7:26 am and sunset at 7:09 pm CDT.

How many hours of sunshine does Summit have in September?

In Summit, the average sunshine duration in September is 9h.

What is the UV index intensity in September?

In September, the average daily maximum UV index is 4. A UV Index value of 3 to 5 symbolizes a medium hazard to health 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
Summit, SD

Average temperature in September - Summit, SD
  • Average high temperature in September: 72.5°F

The warmest month (with the highest average high temperature) is July (81.5°F).
The month with the lowest average high temperature is January (19.6°F).

  • Average low temperature in September: 52.7°F

The month with the highest average low temperature is July (61.9°F).
The coldest month (with the lowest average low temperature) is January (6.1°F).

Average pressure in September
Summit, SD

Average pressure in September - Summit, SD
  • Average pressure in September: 29.97"Hg

The months with the highest atmospheric pressure are January and February (30.16"Hg).
The month with the lowest atmospheric pressure is June (29.86"Hg).

Average wind speed in September
Summit, SD

Average wind speed in September - Summit, SD
  • Average wind speed in September: 9.3mph

The windiest month (with the highest average wind speed) is April (10.7mph).
The calmest month (with the lowest average wind speed) is July (8mph).

Average humidity in September
Summit, SD

Average humidity in September - Summit, SD
  • Average humidity in September: 67%

The month with the highest relative humidity is January (89%).
The month with the lowest relative humidity is October (66%).

Average rainfall in September
Summit, SD

Average rainfall in September - Summit, SD
  • Average rainfall in September: 1.61"

The wettest month (with the highest rainfall) is June (3.11").
The driest months (with the least rainfall) are January and February (0.63").

Average rainfall days in September
Summit, SD

Average rainfall days in September - Summit, SD
  • Average rainfall days in September: 10 days

The month with the highest number of rainy days is June (17.8 days).
The month with the least rainy days is February (2.3 days).

Average snowfall in September
Summit, SD

Average snowfall in September - Summit, SD
  • Average snowfall in September: 0"

The month with the highest snowfall is December (4.49").
The months with the least snowfall are June, July, August and September (0").

Average snowfall days in September
Summit, SD

Average snowfall days in September - Summit, SD
  • Average snowfall days in September: 0 days

The month with the highest number of snowfall days is January (13.1 days).
The months with the least snowfall days are June, July, August and September (0 days).

Average daylight in September /
Average sunshine in September
Summit, SD

Average daylight in September / Average sunshine in September - Summit, SD
  • Average daylight in September: 12h and 3min

The month with the longest days is June (Average daylight: 15h and 36min).
The month with the shortest days is December (Average daylight: 8h and 48min).

  • Average sunshine in September: 9h and 0min

The month with the most sunshine is July (Average sunshine: 10h and 48min).
The month with the least sunshine is January (Average sunshine: 3h and 54min).

Average sunshine days in September
Summit, SD

Average sunshine days in September - Summit, SD
  • Average sunshine days in September: 18 days

The month with the most sunshine days is October (18.5 days).
The month with the least sunshine days is June (9.6 days).

Average UV index in September
Summit, SD

Average UV index in September - Summit, SD
  • Average UV index in September: 4

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
Summit, SD

Average cloud cover in September - Summit, SD
  • Average cloud cover in September: 28

The month with the most cloud cover is January (Cloud cover 58).
The months with the least cloud cover are July and August (Cloud cover 25).

Average visibility in September
Summit, SD

Average visibility in September - Summit, SD
  • Average visibility in September: 6mi

The months with the highest visibility are February, March, April, May, June, July, August, September, October, November and December (6mi).
The month with the lowest visibility is January (5mi).

Summit, South Dakota, USA

Weather forecast for your location

1. Click Locate me button
2. Allow the app to use your location