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 start of September sees the average high-temperature at a still moderately hot 75°F (23.9°C), showing little difference from August's 79.5°F (26.4°C). In September, the temperature in Iroquois, Illinois, drops to an average of 56.8°F (13.8°C) at night.Humidity
In September, the average relative humidity in Iroquois, Illinois, is 78%.Rainfall
In Iroquois, in September, it is raining for 11.3 days, with typically 1.1" (28mm) of accumulated precipitation. In Iroquois, during the entire year, the rain falls for 140.3 days and collects up to 17.56" (446mm) of precipitation.Snowfall
In Iroquois, Illinois, snow does not fall in May through October.Daylight
In Iroquois, the average length of the day in September is 12h and 27min.On the first day of the month, sunrise is at 6:17 am and sunset at 7:22 pm. On the last day of September, sunrise is at 6:46 am and sunset at 6:33 pm CDT.
Sunshine
In September, the average sunshine is 8.5h.UV index
In Iroquois, Illinois, the average daily maximum UV index in September is 5. A UV Index estimate of 3 to 5 represents a medium health hazard from unprotected exposure to Sun's UV rays for average individuals.Note: In September, an average UV index of 5 transforms into the following instructions:
Take necessary precautions - Suggestions to elude sunburn are provided. The mid-day Sun emits the most powerful UV radiation, so seek shade and minimize exposure. Boost your sun resistance with garments that are densely woven yet spacious.
Frequently asked questions
What are the temperatures in Iroquois in September?
What is the average humidity in September in Iroquois?
How much does it rain in Iroquois in September?
When it does not snow in Iroquois?
What is the average length of the day in September in Iroquois?
What time are sunrise and sunset in September in Iroquois?
How many hours of sunshine does Iroquois have in September?
How high is the UV index in September in Iroquois?
Average temperature in September
Iroquois, IL
- Average high temperature in September: 75°F
The warmest month (with the highest average high temperature) is July (81°F).
The month with the lowest average high temperature is January (30.7°F).
- Average low temperature in September: 56.8°F
The month with the highest average low temperature is July (64.2°F).
The coldest month (with the lowest average low temperature) is January (18.9°F).
Average pressure in September
Iroquois, IL
- Average pressure in September: 30.03"Hg
The month with the highest atmospheric pressure is January (30.12"Hg).
The month with the lowest atmospheric pressure is June (29.93"Hg).
Average wind speed in September
Iroquois, IL
- Average wind speed in September: 7.1mph
The windiest month (with the highest average wind speed) is January (10.3mph).
The calmest month (with the lowest average wind speed) is August (6.2mph).
Average humidity in September
Iroquois, IL
- Average humidity in September: 78%
The month with the highest relative humidity is July (85%).
The month with the lowest relative humidity is October (72%).
Average rainfall in September
Iroquois, IL
- Average rainfall in September: 1.1"
The wettest month (with the highest rainfall) is May (2.64").
The driest months (with the least rainfall) are January and February (0.79").
Average rainfall days in September
Iroquois, IL
- Average rainfall days in September: 11.3 days
The month with the highest number of rainy days is July (17.8 days).
The month with the least rainy days is January (4.9 days).
Average snowfall in September
Iroquois, IL
- Average snowfall in September: 0"
The month with the highest snowfall is January (2.05").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in September
Iroquois, IL
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (10.3 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
Iroquois, IL
- Average daylight in September: 12h and 3min
The month with the longest days is June (Average daylight: 15h and 6min).
The month with the shortest days is December (Average daylight: 9h and 18min).
- Average sunshine in September: 8h and 3min
The months with the most sunshine are June and July (Average sunshine: 9h and 48min).
The month with the least sunshine is January (Average sunshine: 3h and 42min).
Average sunshine days in September
Iroquois, IL
- Average sunshine days in September: 15.5 days
The month with the most sunshine days is November (19 days).
The month with the least sunshine days is July (9.4 days).
Average UV index in September
Iroquois, IL
- Average UV index in September: 5
The months with the highest UV index are June and July (UV index 6).
The months with the lowest UV index are January and December (UV index 1).
Average cloud cover in September
Iroquois, IL
- Average cloud cover in September: 34
The month with the most cloud cover is January (Cloud cover 61).
The months with the least cloud cover are July, August and September (Cloud cover 34).
Average visibility in September
Iroquois, 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).
Iroquois, Illinois, USA
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