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
September reveals a small adjustment in temperature, transitioning from an average high of a tropical 87.3°F (30.7°C) in August to a warm 81.7°F (27.6°C). Unionville's temperature lowers to a mean of 61.9°F (16.6°C) during the nights in September.Heat index
In September, the average heat index is computed to be a tropical 86°F (30°C). Prolonged activity during exposure might result in a state of fatigue and cause heat cramps.The standards for the heat index are set for locations in shade and under light breezes. Heat index values might soar by up to 15 Fahrenheit (8 Celsius) degrees with exposure to direct sunshine.
Note: The heat index, also known as 'felt air temperature' or 'apparent temperature', represents the fusion of temperature and moisture in the air to suggest how warm it feels. Additional elements including metabolic differences, the level of physical activity, and attire have a role in shaping the individual's temperature perception. It is noteworthy that being in direct sunlight can enhance the weather's impact, raising the heat index by as much as 15 Fahrenheit (8 Celsius) degrees. Heat index values are essentially critical for children. Kids are usually more vulnerable than adults, given their lesser sweating ability. Along with their larger skin surface relative to their small stature and the excess heat due to their activity, their risk is amplified.
Humidity
In Unionville, Illinois, the average relative humidity in September is 72%.Rainfall
The month with the least rainfall is September, when the rain falls for 8.6 days and typically collects 0.63" (16mm) of precipitation.Snowfall
In Unionville, snow does not fall in April through October.Daylight
In September, the average length of the day is 12h and 25min.On the first day of September, sunrise is at 6:25 am and sunset at 7:22 pm. On the last day of the month, sunrise is at 6:49 am and sunset at 6:38 pm CDT.
Sunshine
In September, the average sunshine is 9.3h.UV index
In Unionville, 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 ordinary individuals.Note: In September, a regular UV index of 5 translates into these guidelines:
Take necessary precautions - Suggestions to elude sunburn are provided. Avoid the Sun's strongest UV rays by seeking shade and limiting exposure during midday. Equip yourself with UVA and UVB-filtering sunglasses on clear, sunny days.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What is the average September temperature?
What is the average humidity in September?
What is the driest month?
How much does it rain in September?
When it does not snow?
How many hours of daylight does Unionville have in September?
When is the sunrise / sunset in September?
How many hours of sunshine does Unionville have in September?
What is the UV index reading in September?
Average temperature in September
Unionville, IL
- Average high temperature in September: 81.7°F
The warmest month (with the highest average high temperature) is July (88.7°F).
The month with the lowest average high temperature is January (41.5°F).
- Average low temperature in September: 61.9°F
The month with the highest average low temperature is July (69.4°F).
The coldest month (with the lowest average low temperature) is January (28.6°F).
Average pressure in September
Unionville, IL
- Average pressure in September: 30.03"Hg
The month with the highest atmospheric pressure is January (30.17"Hg).
The month with the lowest atmospheric pressure is June (29.95"Hg).
Average wind speed in September
Unionville, IL
- Average wind speed in September: 6.3mph
The windiest month (with the highest average wind speed) is April (9mph).
The calmest months (with the lowest average wind speed) are July and August (5.7mph).
Average humidity in September
Unionville, IL
- Average humidity in September: 72%
The months with the highest relative humidity are March and May (79%).
The month with the lowest relative humidity is October (70%).
Average rainfall in September
Unionville, IL
- Average rainfall in September: 0.63"
The wettest month (with the highest rainfall) is May (1.93").
The driest month (with the least rainfall) is September (0.63").
Average rainfall days in September
Unionville, IL
- Average rainfall days in September: 8.6 days
The month with the highest number of rainy days is May (14.7 days).
The month with the least rainy days is October (7.6 days).
Average snowfall in September
Unionville, IL
- Average snowfall in September: 0"
The month with the highest snowfall is February (0.71").
The months with the least snowfall are April, May, June, July, August, September and October (0").
Average snowfall days in September
Unionville, IL
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is February (3.3 days).
The months with the least snowfall days are May, June, July, August, September and October (0 days).
Average daylight in September /
Average sunshine in September
Unionville, IL
- Average daylight in September: 12h and 2min
The month with the longest days is June (Average daylight: 14h and 42min).
The month with the shortest days is December (Average daylight: 9h and 42min).
- Average sunshine in September: 9h and 2min
The months with the most sunshine are June and July (Average sunshine: 10h and 30min).
The month with the least sunshine is February (Average sunshine: 4h and 36min).
Average sunshine days in September
Unionville, IL
- Average sunshine days in September: 19.9 days
The month with the most sunshine days is October (22.3 days).
The month with the least sunshine days is July (14.2 days).
Average UV index in September
Unionville, IL
- Average UV index in September: 5
The months with the highest UV index are May, June, July and August (UV index 6).
The months with the lowest UV index are January and December (UV index 2).
Average cloud cover in September
Unionville, IL
- Average cloud cover in September: 28
The month with the most cloud cover is February (Cloud cover 51).
The months with the least cloud cover are June and September (Cloud cover 28).
Average visibility in September
Unionville, IL
- 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).
Unionville, Illinois, USA
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