September weather forecastMason City, IL
September
Weather in September
The first month of the autumn, September, is also a moderately hot month in Mason City, Illinois, with an average temperature fluctuating between 58.5°F (14.7°C) and 76.8°F (24.9°C).Temperature
At the start of September, Mason City's average high-temperature reaches a still warm 76.8°F (24.9°C), subtly different from the preceding month. During September, Mason City experiences a consistent low-temperature average of 58.5°F (14.7°C).Humidity
In Mason City, the average relative humidity in September is 75%.Rainfall
In Mason City, during September, the rain falls for 12.2 days and regularly aggregates up to 2.56" (65mm) of precipitation. Throughout the year, there are 150 rainfall days, and 29.84" (758mm) of precipitation is accumulated.Snowfall
May through September are months without snowfall.Daylight
In Mason City, the average length of the day in September is 12h and 26min.On the first day of the month, sunrise is at 6:27 am and sunset at 7:30 pm. On the last day of September, sunrise is at 6:54 am and sunset at 6:42 pm CDT.
Sunshine
In September, the average sunshine in Mason City is 9.3h.UV index
In Mason City, 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 radiation for the average person.Note: In September, the UV index of 5 transforms into the following advice:
Proceed with care. Light skin individuals may be exposed to burns in fewer than 30 minutes. UV radiation from the Sun is most dangerous during midday; take precautions and seek shade. Fend off the sun's harsh rays with appropriate clothing, a wide-brim hat, and UV-protective sunglasses.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Mason City, IL
- Average high temperature in September: 76.8°F
The warmest month (with the highest average high temperature) is July (82.4°F).
The month with the lowest average high temperature is January (32°F).
- Average low temperature in September: 58.5°F
The month with the highest average low temperature is July (65.8°F).
The coldest month (with the lowest average low temperature) is January (19.9°F).
Average pressure in September
Mason City, IL
- Average pressure in September: 30.03"Hg
The month with the highest atmospheric pressure is January (30.14"Hg).
The month with the lowest atmospheric pressure is June (29.91"Hg).
Average wind speed in September
Mason City, IL
- Average wind speed in September: 7.3mph
The windiest month (with the highest average wind speed) is April (10.4mph).
The calmest months (with the lowest average wind speed) are July and August (6.3mph).
Average humidity in September
Mason City, IL
- Average humidity in September: 75%
The month with the highest relative humidity is July (84%).
The month with the lowest relative humidity is October (70%).
Average rainfall in September
Mason City, IL
- Average rainfall in September: 2.56"
The wettest month (with the highest rainfall) is May (3.98").
The driest month (with the least rainfall) is December (1.46").
Average rainfall days in September
Mason City, IL
- Average rainfall days in September: 12.2 days
The month with the highest number of rainy days is May (18.9 days).
The month with the least rainy days is February (6.2 days).
Average snowfall in September
Mason City, IL
- Average snowfall in September: 0"
The month with the highest snowfall is January (3.98").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in September
Mason City, IL
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (10.7 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
Mason City, IL
- Average daylight in September: 12h and 24min
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 24min).
- Average sunshine in September: 9h and 18min
The month with the most sunshine is June (Average sunshine: 10h and 18min).
The month with the least sunshine is January (Average sunshine: 4h and 6min).
Average sunshine days in September
Mason City, IL
- Average sunshine days in September: 16.3 days
The month with the most sunshine days is November (18.5 days).
The month with the least sunshine days is May (10.5 days).
Average UV index in September
Mason City, IL
- 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
Mason City, IL
- Average cloud cover in September: 29
The month with the most cloud cover is January (Cloud cover 55).
The months with the least cloud cover are August and September (Cloud cover 29).
Average visibility in September
Mason City, IL
- Average visibility in September: 6mi
The months with the highest visibility are January, February, March, April, May, June, September, October, November and December (6mi).
The months with the lowest visibility are July and August (5mi).
