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
Deerfield's weather subtly changes with the onset of September, barely falling from a warm 77.5°F (25.3°C) in August to an agreeable 71.2°F (21.8°C). Deerfield experiences an average low-temperature of 60.1°F (15.6°C) in the month of September.Humidity
In September, the average relative humidity in Deerfield, Illinois, is 75%.Rainfall
In Deerfield, in September, it is raining for 13.6 days, with typically 2.6" (66mm) of accumulated precipitation. In Deerfield, during the entire year, the rain falls for 154.1 days and collects up to 30.24" (768mm) of precipitation.Snowfall
May through September are months without snowfall.Daylight
In September, the average length of the day is 12h and 28min.On the first day of the month, sunrise is at 6:17 am and sunset at 7:24 pm. On the last day of September, sunrise is at 6:48 am and sunset at 6:34 pm CDT.
Sunshine
The average sunshine in September is 9.2h.UV index
The average daily maximum UV index in September is 4. A UV Index estimate of 3 to 5 represents a medium vulnerability from unsafe exposure to UV radiation for average individuals.Note: In September, the UV index of 4 transforms into the following advice:
Be cautious. Those with fair skin can be subjected to burns in fewer than 30 minutes. For skin protection, it's recommended to minimize Sun exposure during its peak hours around midday. Sunglasses that ward off UVA and UVB rays play a pivotal role in reducing solar eye damage.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What is the temperature in September?
What is the average humidity in September?
How many days does it rain in September?
When it does not snow?
Does it snow in September?
What is the average length of the day in September?
When is the sunrise / sunset in September?
How long on average sun shines in September?
What is the UV index intensity in September?
Average temperature in September
Deerfield, IL
- Average high temperature in September: 71.2°F
The warmest month (with the highest average high temperature) is July (77.7°F).
The month with the lowest average high temperature is January (28.6°F).
- Average low temperature in September: 60.1°F
The months with the highest average low temperature are July and August (66.7°F).
The coldest month (with the lowest average low temperature) is January (18.9°F).
Average pressure in September
Deerfield, IL
- Average pressure in September: 30.03"Hg
The month with the highest atmospheric pressure is January (30.1"Hg).
The month with the lowest atmospheric pressure is June (29.92"Hg).
Average wind speed in September
Deerfield, IL
- Average wind speed in September: 8.9mph
The windiest month (with the highest average wind speed) is January (11.9mph).
The calmest month (with the lowest average wind speed) is August (7.4mph).
Average humidity in September
Deerfield, IL
- Average humidity in September: 75%
The months with the highest relative humidity are January and February (82%).
The month with the lowest relative humidity is October (73%).
Average rainfall in September
Deerfield, IL
- Average rainfall in September: 2.6"
The wettest months (with the highest rainfall) are May and June (3.82").
The driest month (with the least rainfall) is December (1.3").
Average rainfall days in September
Deerfield, IL
- Average rainfall days in September: 13.6 days
The month with the highest number of rainy days is May (17.7 days).
The month with the least rainy days is February (5.9 days).
Average snowfall in September
Deerfield, IL
- Average snowfall in September: 0"
The month with the highest snowfall is January (4.13").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in September
Deerfield, IL
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (11.9 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
Deerfield, IL
- Average daylight in September: 12h and 3min
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 12min).
- Average sunshine in September: 9h and 1min
The month with the most sunshine is August (Average sunshine: 10h and 42min).
The month with the least sunshine is January (Average sunshine: 3h and 48min).
Average sunshine days in September
Deerfield, IL
- Average sunshine days in September: 13.3 days
The month with the most sunshine days is December (15.3 days).
The month with the least sunshine days is April (10.8 days).
Average UV index in September
Deerfield, IL
- Average UV index in September: 4
The months with the highest UV index are June, July and August (UV index 6).
The month with the lowest UV index is December (UV index 1).
Average cloud cover in September
Deerfield, IL
- Average cloud cover in September: 29
The month with the most cloud cover is January (Cloud cover 61).
The months with the least cloud cover are July and August (Cloud cover 27).
Average visibility in September
Deerfield, 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).
Deerfield, Illinois, USA
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