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 introduction of September notes a subtle temperature variation to a still warm 76.8°F (24.9°C) from August's 81.9°F (27.7°C). The average nighttime temperature in Mason City, Illinois, lowers to a mild 58.5°F (14.7°C) throughout September.Humidity
In Mason City, Illinois, the average relative humidity in September is 75%.Rainfall
In September, the rain falls for 12.2 days. Throughout September, 2.56" (65mm) of precipitation is accumulated. Throughout the year, in Mason City, there are 150 rainfall days, and 29.84" (758mm) of precipitation is accumulated.Snowfall
May through September are months without snowfall.Daylight
The average length of the day in September in Mason City 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
The average daily maximum UV index in September is 5. A UV Index value of 3 to 5 symbolizes a moderate health risk from unprotected exposure to Sun's UV rays for the ordinary person.Note: The maximum UV index of 5 during September leads to these instructions:
Exercise caution. The susceptibility of light skin individuals to burns is less than 30 minutes. For health reasons, it's advisable to reduce direct sun exposure during peak hours around midday. Experience reduced UV exposure by about half when donning a wide-brim hat.
Frequently asked questions
What is the average September temperature in Mason City?
What is the average humidity in September in Mason City?
How many days does it rain in September in Mason City?
When it does not snow in Mason City?
Does it snow in Mason City in September?
What is the average length of the day in September in Mason City?
What time are sunrise and sunset in September in Mason City?
How many hours of sunshine does Mason City have in September?
What is the UV index intensity in September in Mason City?
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 2min
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 2min
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).
Mason City, Illinois, USA
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