September weather forecastGarrison, IA
September
Weather in September
September, the first month of the autumn in Garrison, is also an agreeable month, with temperature in the range of an average low of 54.7°F (12.6°C) and an average high of 73.2°F (22.9°C).Temperature
September brings a minor shift in the average high-temperature, adjusting from a moderately hot 79°F (26.1°C) in August to an agreeable 73.2°F (22.9°C). The average temperature in Garrison during September nights dips to a cool 54.7°F (12.6°C).Humidity
The average relative humidity in September in Garrison is 78%.Rainfall
In Garrison, during September, the rain falls for 9.5 days and regularly aggregates up to 1.06" (27mm) of precipitation. In Garrison, during the entire year, the rain falls for 103.1 days and collects up to 10.63" (270mm) of precipitation.Snowfall
May through September are months without snowfall.Daylight
In Garrison, Iowa, the average length of the day in September is 12h and 28min.On the first day of September, sunrise is at 6:34 am and sunset at 7:41 pm. On the last day of the month, sunrise is at 7:05 am and sunset at 6:51 pm CDT.
Sunshine
The average sunshine in September is 9.1h.UV index
The average daily maximum UV index in September in Garrison is 4. A UV Index estimate of 3 to 5 represents a medium health hazard from unprotected exposure to Sun's UV rays for the ordinary person.Note: The maximum UV index, 4 during September, leads to the following recommendations:
Be mindful. Individuals with a lighter skin tone may suffer burns in less than 30 minutes. The Sun's UV radiation is especially harmful around midday, so reduce exposure and stay safe. Boost your sun resistance with garments that are densely woven yet spacious.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Garrison, IA
- Average high temperature in September: 73.2°F
The warmest month (with the highest average high temperature) is July (80.1°F).
The month with the lowest average high temperature is January (25.3°F).
- Average low temperature in September: 54.7°F
The month with the highest average low temperature is July (64.4°F).
The coldest month (with the lowest average low temperature) is January (13.1°F).
Average pressure in September
Garrison, IA
- Average pressure in September: 30.02"Hg
The month with the highest atmospheric pressure is January (30.14"Hg).
The month with the lowest atmospheric pressure is June (29.89"Hg).
Average wind speed in September
Garrison, IA
- Average wind speed in September: 8.1mph
The windiest month (with the highest average wind speed) is April (10.8mph).
The calmest months (with the lowest average wind speed) are July and August (7mph).
Average humidity in September
Garrison, IA
- Average humidity in September: 78%
The month with the highest relative humidity is January (86%).
The month with the lowest relative humidity is October (72%).
Average rainfall in September
Garrison, IA
- Average rainfall in September: 1.06"
The wettest month (with the highest rainfall) is May (1.85").
The driest month (with the least rainfall) is February (0.39").
Average rainfall days in September
Garrison, IA
- Average rainfall days in September: 9.5 days
The month with the highest number of rainy days is June (13.9 days).
The month with the least rainy days is February (3.4 days).
Average snowfall in September
Garrison, IA
- Average snowfall in September: 0"
The month with the highest snowfall is January (1.73").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in September
Garrison, IA
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is February (7.8 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
Garrison, IA
- Average daylight in September: 12h and 30min
The month with the longest days is June (Average daylight: 15h and 12min).
The month with the shortest days is December (Average daylight: 9h and 12min).
- Average sunshine in September: 9h and 6min
The month with the most sunshine is July (Average sunshine: 10h and 0min).
The month with the least sunshine is January (Average sunshine: 3h and 54min).
Average sunshine days in September
Garrison, IA
- Average sunshine days in September: 18.9 days
The month with the most sunshine days is December (21.9 days).
The month with the least sunshine days is June (13.4 days).
Average UV index in September
Garrison, IA
- Average UV index in September: 4
The month with the highest UV index is June (UV index 6).
The month with the lowest UV index is December (UV index 1).
Average cloud cover in September
Garrison, IA
- Average cloud cover in September: 31
The month with the most cloud cover is January (Cloud cover 59).
The months with the least cloud cover are August and September (Cloud cover 31).
Average visibility in September
Garrison, IA
- Average visibility in September: 6mi
The months with the highest visibility are January, February, March, April, May, June, August, September, October, November and December (6mi).
The month with the lowest visibility is July (5mi).
