September weather forecastPorcupine, SD
September
Weather in September
The first month of the autumn, September, is still a warm month in Porcupine, South Dakota, with an average temperature varying between 55.9°F (13.3°C) and 77°F (25°C).Temperature
The beginning of September brings a slight decrease in the average high-temperature, transitioning from a warm 85.6°F (29.8°C) in August to a still moderately hot 77°F (25°C). In Porcupine, the average nighttime temperature during September is a mild 55.9°F (13.3°C).Humidity
In September, the average relative humidity in Porcupine is 49%.Rainfall
In September, the rain falls for 6.1 days. Throughout September, 1.02" (26mm) of precipitation is accumulated. In Porcupine, South Dakota, during the entire year, the rain falls for 86.7 days and collects up to 13.66" (347mm) of precipitation.Snowfall
January through May, September through December are months with snowfall in Porcupine. September is the first month it typically snows in Porcupine. Throughout September, in the average 0.1 snowfall days, it receives 0.04" (1mm) of snow. Throughout the year, there are 47.4 snowfall days, and 22.72" (577mm) of snow is accumulated.Daylight
In Porcupine, the average length of the day in September is 12h and 29min.On the first day of September, sunrise is at 6:14 am and sunset at 7:23 pm. On the last day of the month, sunrise is at 6:46 am and sunset at 6:31 pm MDT.
Sunshine
The average sunshine in September is 10.2h.UV index
The average daily maximum UV index in September in Porcupine is 4. A UV Index of 3 to 5 symbolizes a medium vulnerability from exposure to the Sun's UV radiation for average individuals.Note: An average UV index of 4 in September transforms into this advice:
Take heed. Individuals of lighter complexion can be burned in less than half an hour. Considering the harmful UV rays from the Sun during midday, it's essential to reduce exposure. Select sunglasses that boast both UVA and UVB protection to limit the adverse effects of the sun on the eyes. Watch out! The Sun's UV radiation can be nearly magnified twofold due to snow reflection.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Porcupine, SD
- Average high temperature in September: 77°F
The warmest month (with the highest average high temperature) is July (87.6°F).
The month with the lowest average high temperature is December (32.4°F).
- Average low temperature in September: 55.9°F
The month with the highest average low temperature is July (65.5°F).
The coldest month (with the lowest average low temperature) is January (18.1°F).
Average pressure in September
Porcupine, SD
- Average pressure in September: 29.94"Hg
The month with the highest atmospheric pressure is January (30.13"Hg).
The month with the lowest atmospheric pressure is June (29.85"Hg).
Average wind speed in September
Porcupine, SD
- Average wind speed in September: 11.2mph
The windiest month (with the highest average wind speed) is April (12.2mph).
The calmest month (with the lowest average wind speed) is August (10.2mph).
Average humidity in September
Porcupine, SD
- Average humidity in September: 49%
The month with the highest relative humidity is January (80%).
The month with the lowest relative humidity is August (48%).
Average rainfall in September
Porcupine, SD
- Average rainfall in September: 1.02"
The wettest month (with the highest rainfall) is May (2.13").
The driest month (with the least rainfall) is January (0.55").
Average rainfall days in September
Porcupine, SD
- Average rainfall days in September: 6.1 days
The month with the highest number of rainy days is May (13.1 days).
The months with the least rainy days are February and December (2.5 days).
Average snowfall in September
Porcupine, SD
- Average snowfall in September: 0.04"
The month with the highest snowfall is February (4.02").
The months with the least snowfall are June, July and August (0").
Average snowfall days in September
Porcupine, SD
- Average snowfall days in September: 0.1 days
The month with the highest number of snowfall days is February (11.5 days).
The months with the least snowfall days are June, July and August (0 days).
Average daylight in September /
Average sunshine in September
Porcupine, SD
- Average daylight in September: 12h and 30min
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 0min).
- Average sunshine in September: 10h and 12min
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 12min).
Average sunshine days in September
Porcupine, SD
- Average sunshine days in September: 22.8 days
The month with the most sunshine days is September (22.8 days).
The month with the least sunshine days is April (13.2 days).
Average UV index in September
Porcupine, SD
- Average UV index in September: 4
The month with the highest UV index is July (UV index 7).
The months with the lowest UV index are January, February, November and December (UV index 2).
Average cloud cover in September
Porcupine, SD
- Average cloud cover in September: 19
The month with the most cloud cover is February (Cloud cover 44).
The month with the least cloud cover is August (Cloud cover 16).
Average visibility in September
Porcupine, 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).
