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 sees a slight reduction in average high-temperature, with a shift from a warm 80.1°F (26.7°C) in August to a still moderately hot 73.9°F (23.3°C). The nighttime temperature in Markham, Illinois, dips to a mild 58.3°F (14.6°C) on average during September.Humidity
The average relative humidity in September is 76%.Rainfall
In Markham, in September, during 13.4 rainfall days, 2.48" (63mm) of precipitation is typically accumulated. In Markham, during the entire year, the rain falls for 155.6 days and collects up to 31.3" (795mm) of precipitation.Snowfall
May through September are months without snowfall in Markham, Illinois.Daylight
In Markham, Illinois, the average length of the day in September is 12h and 28min.On the first day of the month, sunrise is at 6:17 am and sunset at 7:23 pm. On the last day of September, in Markham, sunrise is at 6:47 am and sunset at 6:33 pm CDT.
Sunshine
The average sunshine in September in Markham, Illinois, is 8.8h.UV index
In Markham, Illinois, the average daily maximum UV index in September is 4. A UV Index reading of 3 to 5 represents a medium vulnerability from unprotected exposure to Sun's UV rays for the average person.Note: The maximum UV index, 4 during September, leads to the following recommendations:
Guard yourself - An obligation to protect skin and eyes from harm exists. Considering the Sun's intensity during midday, it's wise to minimize direct exposure. To best shield against UV radiation, choose sun-safe garments and dependable sunglasses.
Frequently asked questions
What is the average September temperature in Markham?
What is the average humidity in September in Markham?
How much does it rain in Markham in September?
When it does not snow in Markham?
Does it snow in Markham in September?
How many hours of daylight does Markham have in September?
When are sunrise and sunset in September in Markham?
How long on average sun shines in September in Markham?
How high is the UV index in September in Markham?
Average temperature in September
Markham, IL
- Average high temperature in September: 73.9°F
The warmest month (with the highest average high temperature) is July (81.3°F).
The month with the lowest average high temperature is January (29.7°F).
- Average low temperature in September: 58.3°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 (18.9°F).
Average pressure in September
Markham, IL
- Average pressure in September: 30.03"Hg
The month with the highest atmospheric pressure is January (30.11"Hg).
The month with the lowest atmospheric pressure is June (29.92"Hg).
Average wind speed in September
Markham, IL
- Average wind speed in September: 7.3mph
The windiest month (with the highest average wind speed) is January (10.2mph).
The calmest month (with the lowest average wind speed) is August (6.3mph).
Average humidity in September
Markham, IL
- Average humidity in September: 76%
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
Markham, IL
- Average rainfall in September: 2.48"
The wettest month (with the highest rainfall) is May (4.17").
The driest month (with the least rainfall) is December (1.54").
Average rainfall days in September
Markham, IL
- Average rainfall days in September: 13.4 days
The month with the highest number of rainy days is July (17.6 days).
The month with the least rainy days is February (6.1 days).
Average snowfall in September
Markham, IL
- Average snowfall in September: 0"
The month with the highest snowfall is January (4.53").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in September
Markham, IL
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (12.6 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Markham, 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 12min).
- Average sunshine in September: 8h and 5min
The month with the most sunshine is August (Average sunshine: 10h and 6min).
The month with the least sunshine is January (Average sunshine: 3h and 36min).
Average sunshine days in September
Markham, IL
- Average sunshine days in September: 14 days
The month with the most sunshine days is November (16.4 days).
The month with the least sunshine days is April (10.2 days).
Average UV index in September
Markham, IL
- Average UV index in September: 4
The months with the highest UV index are June and July (UV index 6).
The month with the lowest UV index is December (UV index 1).
Average cloud cover in September
Markham, IL
- Average cloud cover in September: 32
The month with the most cloud cover is January (Cloud cover 62).
The month with the least cloud cover is August (Cloud cover 30).
Average visibility in September
Markham, IL
- Average visibility in September: 6mi
The months with the highest visibility are February, March, April, May, June, July, August, September, October, November and December (6mi).
The month with the lowest visibility is January (5mi).
Markham, Illinois, USA
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