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 involves a subtle temperature drop, shifting from a warm 79.3°F (26.3°C) in August to an agreeable 72.9°F (22.7°C). Throughout the nights in September, Vernon Hills experiences an average low-temperature of 57.4°F (14.1°C).Humidity
In September, the average relative humidity is 76%.Rainfall
In Vernon Hills, during September, the rain falls for 12.9 days and regularly aggregates up to 2.05" (52mm) of precipitation. Throughout the year, there are 147.3 rainfall days, and 27.44" (697mm) of precipitation is accumulated.Snowfall
In Vernon Hills, snow does not fall in June through September.Daylight
In September, the average length of the day is 12h and 28min.On the first day of the month, sunrise is at 6:18 am and sunset at 7:25 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 9h.UV index
In September, the average daily maximum UV index is 4. A UV Index value of 3 to 5 symbolizes a medium vulnerability from exposure to the Sun's UV rays for average individuals.Note: In September, the maximum UV index of 4 translates into these guidelines:
Be mindful. Those with pale skin might receive burns in fewer than 30 minutes. The Sun's UV radiation is especially harmful around midday, so reduce exposure and stay safe. Safeguard your eyes, ears, and face from sun rays with the aid of a wide-brim hat.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What is the usual temperature for Vernon Hills in September?
What is the average humidity in September?
How much does it rain in September?
When it does not snow in Vernon Hills?
Does it snow in Vernon Hills in September?
What is the average length of the day in September?
When are sunrise and sunset in September?
How long on average sun shines in September?
What is the UV index intensity in September?
Average temperature in September
Vernon Hills, IL
- Average high temperature in September: 72.9°F
The warmest month (with the highest average high temperature) is July (80.4°F).
The month with the lowest average high temperature is January (27.9°F).
- Average low temperature in September: 57.4°F
The month with the highest average low temperature is July (64.9°F).
The coldest month (with the lowest average low temperature) is January (16.5°F).
Average pressure in September
Vernon Hills, 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
Vernon Hills, IL
- Average wind speed in September: 7.5mph
The windiest month (with the highest average wind speed) is January (10.3mph).
The calmest month (with the lowest average wind speed) is August (6.4mph).
Average humidity in September
Vernon Hills, IL
- Average humidity in September: 76%
The months with the highest relative humidity are January and February (83%).
The month with the lowest relative humidity is October (74%).
Average rainfall in September
Vernon Hills, IL
- Average rainfall in September: 2.05"
The wettest month (with the highest rainfall) is June (3.54").
The driest months (with the least rainfall) are November and December (1.3").
Average rainfall days in September
Vernon Hills, IL
- Average rainfall days in September: 12.9 days
The month with the highest number of rainy days is May (17.8 days).
The month with the least rainy days is February (4.3 days).
Average snowfall in September
Vernon Hills, IL
- Average snowfall in September: 0"
The month with the highest snowfall is February (5.55").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in September
Vernon Hills, IL
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (12.9 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Vernon Hills, 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 0min
The months with the most sunshine are July and August (Average sunshine: 10h and 6min).
The month with the least sunshine is January (Average sunshine: 3h and 42min).
Average sunshine days in September
Vernon Hills, IL
- Average sunshine days in September: 14.5 days
The month with the most sunshine days is November (16.6 days).
The month with the least sunshine days is June (10 days).
Average UV index in September
Vernon Hills, IL
- Average UV index in September: 4
The months with the highest UV index are July and August (UV index 6).
The month with the lowest UV index is December (UV index 1).
Average cloud cover in September
Vernon Hills, IL
- Average cloud cover in September: 31
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 30).
Average visibility in September
Vernon Hills, IL
- Average visibility in September: 6mi
The months with the highest visibility are March, April, May, June, July, August, September, October, November and December (6mi).
The months with the lowest visibility are January and February (5mi).
Vernon Hills, Illinois, USA
Weather forecast for your location
2. Allow the app to use your location