September weather forecastDenmark, IA
September
Weather in September
The first month of the autumn, September, is also a moderately hot month in Denmark, Iowa, with an average temperature varying between 57.4°F (14.1°C) and 77°F (25°C).Temperature
September registers an average high-temperature of a still warm 77°F (25°C), slightly varied from August's 82.2°F (27.9°C). In the month of September, the average temperature dips to a moderate 57.4°F (14.1°C) during the night.Humidity
In September, the average relative humidity is 74%.Rainfall
In September, the rain falls for 8.2 days. Throughout September, 0.83" (21mm) of precipitation is accumulated. In Denmark, during the entire year, the rain falls for 101.8 days and collects up to 9.92" (252mm) of precipitation.Snowfall
May through September are months without snowfall.Daylight
The average length of the day in September in Denmark is 12h and 27min.On the first day of September, sunrise is at 6:33 am and sunset at 7:37 pm. On the last day of the month, sunrise is at 7:01 am and sunset at 6:48 pm CDT.
Sunshine
In September, the average sunshine is 9.6h.UV index
In September, the average daily maximum UV index is 4. A UV Index value of 3 to 5 symbolizes a moderate health risk from exposure to the Sun's UV radiation for the average person.Note: In September, the UV index of 4 transforms into the following advice:
Undertake protective steps - Obligation to safeguard skin and eyes from harm is in place. Considering the harmful UV rays from the Sun during midday, it's essential to reduce exposure. To mitigate harm from sun exposure, pick sunglasses offering UVA and UVB defense.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Denmark, IA
- Average high temperature in September: 77°F
The warmest month (with the highest average high temperature) is July (82.9°F).
The month with the lowest average high temperature is January (30.4°F).
- Average low temperature in September: 57.4°F
The month with the highest average low temperature is July (66.2°F).
The coldest month (with the lowest average low temperature) is January (18.5°F).
Average pressure in September
Denmark, IA
- Average pressure in September: 30.02"Hg
The month with the highest atmospheric pressure is January (30.15"Hg).
The month with the lowest atmospheric pressure is June (29.9"Hg).
Average wind speed in September
Denmark, IA
- Average wind speed in September: 7.7mph
The windiest months (with the highest average wind speed) are January, February, March and April (10.4mph).
The calmest months (with the lowest average wind speed) are July and August (6.7mph).
Average humidity in September
Denmark, IA
- Average humidity in September: 74%
The month with the highest relative humidity is July (82%).
The month with the lowest relative humidity is October (71%).
Average rainfall in September
Denmark, IA
- Average rainfall in September: 0.83"
The wettest month (with the highest rainfall) is May (1.46").
The driest months (with the least rainfall) are January and December (0.47").
Average rainfall days in September
Denmark, IA
- Average rainfall days in September: 8.2 days
The month with the highest number of rainy days is May (14.4 days).
The month with the least rainy days is February (3.5 days).
Average snowfall in September
Denmark, IA
- Average snowfall in September: 0"
The month with the highest snowfall is January (1.1").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in September
Denmark, IA
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (7.7 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
Denmark, IA
- Average daylight in September: 12h and 30min
The month with the longest days is June (Average daylight: 15h and 0min).
The month with the shortest days is December (Average daylight: 9h and 18min).
- Average sunshine in September: 9h and 36min
The month with the most sunshine is July (Average sunshine: 10h and 24min).
The month with the least sunshine is January (Average sunshine: 4h and 18min).
Average sunshine days in September
Denmark, IA
- Average sunshine days in September: 19.4 days
The month with the most sunshine days is December (22.9 days).
The month with the least sunshine days is May (14 days).
Average UV index in September
Denmark, IA
- Average UV index in September: 4
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
Denmark, IA
- Average cloud cover in September: 28
The month with the most cloud cover is January (Cloud cover 54).
The months with the least cloud cover are July, August and September (Cloud cover 28).
Average visibility in September
Denmark, IA
- 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).





