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
The transition into September subtly indicates a reduction in the average high-temperature, down to a still moderately hot 76.3°F (24.6°C) from August's 85.1°F (29.5°C). During the month of September, Harrison experiences a steady low-temperature average of 55.4°F (13°C).Humidity
The average relative humidity in September is 63%.Rainfall
In September, the rain falls for 9.4 days. Throughout September, 1.02" (26mm) of precipitation is accumulated. In Harrison, during the entire year, the rain falls for 104.1 days and collects up to 14.29" (363mm) of precipitation.Snowfall
In Harrison, snow does not fall in May through September.Daylight
In Harrison, the average length of the day in September is 12h and 29min.On the first day of the month, sunrise is at 6:58 am and sunset at 8:08 pm. On the last day of September, sunrise is at 7:31 am and sunset at 7:16 pm CDT.
Sunshine
In September, the average sunshine is 8.9h.UV index
The average daily maximum UV index in September is 5. A UV Index of 3 to 5 symbolizes a moderate health risk from exposure to the Sun's UV rays for average individuals.Note: In September, a daily maximum UV index of 5 leads to the following instructions:
Heed the precautions - Protecting the skin and eyes from damage is compulsory. Minimize direct exposure to the Sun during midday when its radiation is at its peak. Stay sun-safe with clothing that is both closely woven and worn loosely.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What are the temperatures in Harrison in September?
What is the average humidity in September?
How much does it rain in September?
When it does not snow?
Does it snow in September?
What is the average length of the day in September?
When are sunrise and sunset in September?
How long on average sun shines in September?
What is the UV index reading in September?
Average temperature in September
Harrison, SD
- Average high temperature in September: 76.3°F
The warmest month (with the highest average high temperature) is July (86.5°F).
The month with the lowest average high temperature is January (27.3°F).
- Average low temperature in September: 55.4°F
The month with the highest average low temperature is July (65.7°F).
The coldest month (with the lowest average low temperature) is January (13.6°F).
Average pressure in September
Harrison, SD
- Average pressure in September: 29.96"Hg
The month with the highest atmospheric pressure is January (30.16"Hg).
The month with the lowest atmospheric pressure is June (29.85"Hg).
Average wind speed in September
Harrison, SD
- Average wind speed in September: 9.4mph
The windiest month (with the highest average wind speed) is April (11.1mph).
The calmest month (with the lowest average wind speed) is July (8.3mph).
Average humidity in September
Harrison, SD
- Average humidity in September: 63%
The month with the highest relative humidity is January (84%).
The month with the lowest relative humidity is October (62%).
Average rainfall in September
Harrison, SD
- Average rainfall in September: 1.02"
The wettest month (with the highest rainfall) is May (2.72").
The driest month (with the least rainfall) is February (0.31").
Average rainfall days in September
Harrison, SD
- Average rainfall days in September: 9.4 days
The month with the highest number of rainy days is May (15.3 days).
The month with the least rainy days is January (2.9 days).
Average snowfall in September
Harrison, SD
- Average snowfall in September: 0"
The months with the highest snowfall are January and March (1.93").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in September
Harrison, SD
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (8.2 days).
The months with the least snowfall days are May, June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Harrison, SD
- Average daylight in September: 12h and 3min
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: 8h and 5min
The month with the most sunshine is July (Average sunshine: 11h and 6min).
The month with the least sunshine is January (Average sunshine: 4h and 42min).
Average sunshine days in September
Harrison, SD
- Average sunshine days in September: 18.4 days
The month with the most sunshine days is November (23.4 days).
The month with the least sunshine days is June (12.3 days).
Average UV index in September
Harrison, SD
- Average UV index in September: 5
The months with the highest UV index are June, July and August (UV index 6).
The months with the lowest UV index are January, February, November and December (UV index 2).
Average cloud cover in September
Harrison, SD
- Average cloud cover in September: 24
The month with the most cloud cover is January (Cloud cover 49).
The month with the least cloud cover is July (Cloud cover 23).
Average visibility in September
Harrison, 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).
Harrison, South Dakota, USA
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