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
September's arrival comes with a mild decrease in the average high-temperature, moving subtly from 82.8°F (28.2°C) in August to a still warm 73.9°F (23.3°C). September nights observe an average temperature dip to a cool 54°F (12.2°C).Humidity
August and September, with an average relative humidity of 50%, are the least humid months.Rainfall
In September, the rain falls for 7.8 days. Throughout September, 0.94" (24mm) of precipitation is accumulated. Throughout the year, there are 118.8 rainfall days, and 15.39" (391mm) of precipitation is accumulated.Snowfall
January through May, September through December are months with snowfall. September is the first month it typically snows. Throughout September, in the average 0.1 snowfall days, it receives 0.12" (3mm) of snow. In Piedmont, during the entire year, snow falls for 50.4 days and aggregates up to 24.41" (620mm) of snow.Daylight
In Piedmont, South Dakota, the average length of the day in September is 12h and 30min.On the first day of the month, sunrise is at 6:17 am and sunset at 7:29 pm. On the last day of September, sunrise is at 6:51 am and sunset at 6:35 pm MDT.
Sunshine
The average sunshine in September is 10.4h.UV index
The average daily maximum UV index in September in Piedmont is 4. A UV Index of 3 to 5 symbolizes a moderate health risk from unsafe exposure to UV radiation for the average person.Note: An average UV index of 4 in September transforms into this advice:
Preventative actions are necessary - Recommendations to ward off sunburn are given. The midday Sun can be harmful due to its potent UV radiation; seek shade and reduce exposure. Sun-related eye harm can be minimized with proper sunglasses offering UVA and UVB coverage. Be vigilant! The reflective nature of snow can increase the Sun's UV radiation nearly twofold.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What are September temperatures?
What is the least humid month?
What is the average humidity in September?
How much does it rain in September?
When does it start to snow?
How many hours of daylight does Piedmont have in September?
When are sunrise and sunset in September?
How long on average sun shines in September?
What is the UV index intensity in September?
Average temperature in September
Piedmont, SD
- Average high temperature in September: 73.9°F
The warmest month (with the highest average high temperature) is July (84.7°F).
The month with the lowest average high temperature is December (32.5°F).
- Average low temperature in September: 54°F
The month with the highest average low temperature is July (63.3°F).
The coldest month (with the lowest average low temperature) is February (17.8°F).
Average pressure in September
Piedmont, SD
- Average pressure in September: 29.93"Hg
The month with the highest atmospheric pressure is January (30.14"Hg).
The month with the lowest atmospheric pressure is June (29.84"Hg).
Average wind speed in September
Piedmont, SD
- Average wind speed in September: 9.1mph
The windiest month (with the highest average wind speed) is April (10.3mph).
The calmest month (with the lowest average wind speed) is August (8.2mph).
Average humidity in September
Piedmont, SD
- Average humidity in September: 50%
The month with the highest relative humidity is January (77%).
The months with the lowest relative humidity are August and September (50%).
Average rainfall in September
Piedmont, SD
- Average rainfall in September: 0.94"
The wettest month (with the highest rainfall) is May (2.28").
The driest month (with the least rainfall) is January (0.43").
Average rainfall days in September
Piedmont, SD
- Average rainfall days in September: 7.8 days
The month with the highest number of rainy days is May (17.1 days).
The month with the least rainy days is December (4.8 days).
Average snowfall in September
Piedmont, SD
- Average snowfall in September: 0.12"
The month with the highest snowfall is April (5.43").
The months with the least snowfall are June, July and August (0").
Average snowfall days in September
Piedmont, SD
- Average snowfall days in September: 0.1 days
The month with the highest number of snowfall days is February (10.5 days).
The months with the least snowfall days are June, July and August (0 days).
Average daylight in September /
Average sunshine in September
Piedmont, SD
- Average daylight in September: 12h and 3min
The month with the longest days is June (Average daylight: 15h and 30min).
The month with the shortest days is December (Average daylight: 8h and 54min).
- Average sunshine in September: 10h and 2min
The month with the most sunshine is August (Average sunshine: 11h and 48min).
The month with the least sunshine is February (Average sunshine: 5h and 54min).
Average sunshine days in September
Piedmont, SD
- Average sunshine days in September: 19.9 days
The month with the most sunshine days is November (20.2 days).
The month with the least sunshine days is May (11 days).
Average UV index in September
Piedmont, 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, February, November and December (UV index 2).
Average cloud cover in September
Piedmont, SD
- Average cloud cover in September: 18
The months with the most cloud cover are February and April (Cloud cover 38).
The month with the least cloud cover is August (Cloud cover 16).
Average visibility in September
Piedmont, 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).
Piedmont, South Dakota, USA
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