September weather forecastLong Valley, SD
September
Weather in September
September, the first month of the autumn in Long Valley, is also a moderately hot month, with temperature in the range of an average high of 77.5°F (25.3°C) and an average low of 58.3°F (14.6°C).Temperature
With the onset of September, Long Valley's average high-temperature adjusts, receding from August's tropical 87.1°F (30.6°C) to a warm 77.5°F (25.3°C). Long Valley's nighttime temperature in September falls to an average of 58.3°F (14.6°C).Humidity
With an average relative humidity of 47%, September is the least humid month in Long Valley.Rainfall
In Long Valley, in September, during 8.5 rainfall days, 0.91" (23mm) of precipitation is typically accumulated. In Long Valley, during the entire year, the rain falls for 95.3 days and collects up to 13.74" (349mm) of precipitation.Snowfall
June through September are months without snowfall.Daylight
In Long Valley, the average length of the day in September is 12h and 29min.On the first day of the month, sunrise is at 6:10 am and sunset at 7:20 pm. On the last day of September, sunrise is at 6:43 am and sunset at 6:28 pm MDT.
Sunshine
The average sunshine in September is 9.9h.UV index
In September, the average daily maximum UV index is 5. A UV Index value of 3 to 5 symbolizes a medium vulnerability from unprotected exposure to Sun's UV rays for average individuals.Note: The maximum daily UV index of 5 in September converts into the following recommendations:
Undertake protective steps - Obligation to safeguard skin and eyes from harm is in place. For health reasons, it's advisable to reduce direct sun exposure during peak hours around midday. To cut down UV radiation exposure by about half, sport a wide-brim hat.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Long Valley, SD
- Average high temperature in September: 77.5°F
The warmest month (with the highest average high temperature) is July (89.2°F).
The month with the lowest average high temperature is January (29.8°F).
- Average low temperature in September: 58.3°F
The month with the highest average low temperature is July (68.5°F).
The coldest month (with the lowest average low temperature) is January (16.7°F).
Average pressure in September
Long Valley, SD
- Average pressure in September: 29.94"Hg
The month with the highest atmospheric pressure is January (30.15"Hg).
The month with the lowest atmospheric pressure is June (29.85"Hg).
Average wind speed in September
Long Valley, SD
- Average wind speed in September: 11.1mph
The windiest month (with the highest average wind speed) is April (12.1mph).
The calmest month (with the lowest average wind speed) is February (10.1mph).
Average humidity in September
Long Valley, SD
- Average humidity in September: 47%
The month with the highest relative humidity is January (81%).
The month with the lowest relative humidity is September (47%).
Average rainfall in September
Long Valley, SD
- Average rainfall in September: 0.91"
The wettest month (with the highest rainfall) is May (2.09").
The driest month (with the least rainfall) is January (0.39").
Average rainfall days in September
Long Valley, SD
- Average rainfall days in September: 8.5 days
The month with the highest number of rainy days is May (13.5 days).
The month with the least rainy days is February (2.6 days).
Average snowfall in September
Long Valley, SD
- Average snowfall in September: 0"
The month with the highest snowfall is February (3.15").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in September
Long Valley, SD
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is February (8.9 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Long Valley, SD
- Average daylight in September: 12h and 30min
The month with the longest days is June (Average daylight: 15h and 24min).
The month with the shortest days is December (Average daylight: 9h and 0min).
- Average sunshine in September: 9h and 54min
The month with the most sunshine is August (Average sunshine: 11h and 42min).
The months with the least sunshine are January and February (Average sunshine: 5h and 12min).
Average sunshine days in September
Long Valley, SD
- Average sunshine days in September: 18.8 days
The month with the most sunshine days is December (21.1 days).
The months with the least sunshine days are April and June (14.1 days).
Average UV index in September
Long Valley, SD
- Average UV index in September: 5
The month with the highest UV index is July (UV index 7).
The month with the lowest UV index is December (UV index 1).
Average cloud cover in September
Long Valley, SD
- Average cloud cover in September: 19
The month with the most cloud cover is January (Cloud cover 46).
The months with the least cloud cover are July and August (Cloud cover 18).
Average visibility in September
Long Valley, 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).
