September weather forecastSaint Donatus, IA
September
Weather in September
The first month of the autumn, September, is still a pleasant month in Saint Donatus, Iowa, with an average temperature varying between 73°F (22.8°C) and 54°F (12.2°C).Temperature
The beginning of September brings a minor change in the average high-temperature, shifting from a warm 79°F (26.1°C) in August to a pleasant 73°F (22.8°C). Saint Donatus reports an average nighttime low-temperature of 54°F (12.2°C) in September.Humidity
In September, the average relative humidity is 79%.Rainfall
In Saint Donatus, in September, during 12.4 rainfall days, 2.4" (61mm) of precipitation is typically accumulated. In Saint Donatus, during the entire year, the rain falls for 145.6 days and collects up to 28.9" (734mm) of precipitation.Snowfall
May through September are months without snowfall in Saint Donatus.Daylight
In September, the average length of the day in Saint Donatus is 12h and 28min.On the first day of the month, sunrise is at 6:28 am and sunset at 7:35 pm. On the last day of September, sunrise is at 6:58 am and sunset at 6:44 pm CDT.
Sunshine
In September, the average sunshine is 9.1h.UV index
In Saint Donatus, the average daily maximum UV index in September is 4. A UV Index estimate of 3 to 5 represents a moderate health risk from exposure to the Sun's UV radiation for the average person.Note: A maximum high daily UV index of 4 during September translates into the following directions:
Undertake precautions - It is suggested to shield oneself from sunburn. The best time to avoid the Sun's harmful UV radiation is during midday when it's most potent. A wide-brimmed hat is a staple for defending the face, eyes, ears, and neck from the Sun.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Saint Donatus, IA
- Average high temperature in September: 73°F
The warmest month (with the highest average high temperature) is July (79.9°F).
The month with the lowest average high temperature is January (25.7°F).
- Average low temperature in September: 54°F
The month with the highest average low temperature is July (63.5°F).
The coldest month (with the lowest average low temperature) is January (13.1°F).
Average pressure in September
Saint Donatus, IA
- Average pressure in September: 30.02"Hg
The month with the highest atmospheric pressure is January (30.13"Hg).
The month with the lowest atmospheric pressure is June (29.9"Hg).
Average wind speed in September
Saint Donatus, IA
- Average wind speed in September: 7.6mph
The windiest month (with the highest average wind speed) is April (10.3mph).
The calmest month (with the lowest average wind speed) is August (6.6mph).
Average humidity in September
Saint Donatus, IA
- Average humidity in September: 79%
The month with the highest relative humidity is January (87%).
The month with the lowest relative humidity is October (75%).
Average rainfall in September
Saint Donatus, IA
- Average rainfall in September: 2.4"
The wettest month (with the highest rainfall) is May (4.13").
The driest month (with the least rainfall) is January (1.22").
Average rainfall days in September
Saint Donatus, IA
- Average rainfall days in September: 12.4 days
The month with the highest number of rainy days is May (19.8 days).
The month with the least rainy days is February (4.5 days).
Average snowfall in September
Saint Donatus, IA
- Average snowfall in September: 0"
The month with the highest snowfall is January (4.61").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in September
Saint Donatus, IA
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (10.6 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
Saint Donatus, 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 6min).
- Average sunshine in September: 9h and 6min
The month with the most sunshine is July (Average sunshine: 9h and 54min).
The month with the least sunshine is January (Average sunshine: 3h and 42min).
Average sunshine days in September
Saint Donatus, IA
- Average sunshine days in September: 15.9 days
The month with the most sunshine days is November (19 days).
The month with the least sunshine days is May (9.5 days).
Average UV index in September
Saint Donatus, IA
- Average UV index in September: 4
The month with the highest UV index is July (UV index 6).
The months with the lowest UV index are January and December (UV index 1).
Average cloud cover in September
Saint Donatus, IA
- Average cloud cover in September: 32
The month with the most cloud cover is January (Cloud cover 61).
The months with the least cloud cover are August and September (Cloud cover 32).
Average visibility in September
Saint Donatus, IA
- Average visibility in September: 6mi
The months with the highest visibility are February, March, April, May, June, August, September, October, November and December (6mi).
The months with the lowest visibility are January and July (5mi).
