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 onset of September results in a small decrease in the average high-temperature, moderately receding from a warm 79.3°F (26.3°C) in August to a still moderately hot 73.9°F (23.3°C). In September, Nelson experiences an average nighttime temperature of 55.2°F (12.9°C).Humidity
In September, the average relative humidity in Nelson is 78%.Rainfall
In Nelson, during September, the rain falls for 9.7 days and regularly aggregates up to 1.26" (32mm) of precipitation. Throughout the year, in Nelson, Illinois, there are 130.2 rainfall days, and 17.36" (441mm) of precipitation is accumulated.Snowfall
In Nelson, snow does not fall in May through September.Daylight
The average length of the day in September is 12h and 28min.On the first day of the month, sunrise is at 6:25 am and sunset at 7:31 pm. On the last day of September, in Nelson, sunrise is at 6:55 am and sunset at 6:41 pm CDT.
Sunshine
The average sunshine in September in Nelson is 9.1h.UV index
In Nelson, the average daily maximum UV index in September is 4. A UV Index reading of 3 to 5 represents a medium vulnerability from exposure to the Sun's UV rays for average individuals.Note: The maximum UV index of 4 during September leads to these instructions:
Be mindful. Those with pale skin might receive burns in fewer than 30 minutes. The Sun's harshest UV rays are around midday; it's wise to seek shade and limit time outdoors. Your best bet for sun defense on the face, eyes, and neck is a hat with a wide brim.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What is the average September temperature in Nelson?
What is the average humidity in September in Nelson?
How many days does it rain in September in Nelson?
When it does not snow in Nelson?
Does it snow in Nelson in September?
What is the average length of the day in September in Nelson?
What time are sunrise and sunset in September in Nelson?
How many hours of sunshine does Nelson have in September?
What is the UV index reading in September in Nelson?
Average temperature in September
Nelson, IL
- Average high temperature in September: 73.9°F
The warmest month (with the highest average high temperature) is July (80.2°F).
The month with the lowest average high temperature is January (27.7°F).
- Average low temperature in September: 55.2°F
The month with the highest average low temperature is July (63.9°F).
The coldest month (with the lowest average low temperature) is January (14.9°F).
Average pressure in September
Nelson, 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 (29.91"Hg).
Average wind speed in September
Nelson, IL
- Average wind speed in September: 7.6mph
The windiest month (with the highest average wind speed) is April (10.4mph).
The calmest month (with the lowest average wind speed) is August (6.4mph).
Average humidity in September
Nelson, IL
- Average humidity in September: 78%
The months with the highest relative humidity are January and July (85%).
The month with the lowest relative humidity is October (73%).
Average rainfall in September
Nelson, IL
- Average rainfall in September: 1.26"
The wettest month (with the highest rainfall) is May (2.83").
The driest months (with the least rainfall) are January and February (0.75").
Average rainfall days in September
Nelson, IL
- Average rainfall days in September: 9.7 days
The month with the highest number of rainy days is May (17.3 days).
The month with the least rainy days is January (4.8 days).
Average snowfall in September
Nelson, IL
- Average snowfall in September: 0"
The month with the highest snowfall is January (2.56").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in September
Nelson, IL
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (10.2 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
Nelson, 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 July (Average sunshine: 9h and 48min).
The month with the least sunshine is January (Average sunshine: 3h and 48min).
Average sunshine days in September
Nelson, IL
- Average sunshine days in September: 18.4 days
The months with the most sunshine days are November and December (18.8 days).
The month with the least sunshine days is June (11.3 days).
Average UV index in September
Nelson, IL
- Average UV index in September: 4
The month with the highest UV index is July (UV index 6).
The month with the lowest UV index is December (UV index 1).
Average cloud cover in September
Nelson, IL
- Average cloud cover in September: 31
The month with the most cloud cover is January (Cloud cover 60).
The month with the least cloud cover is September (Cloud cover 31).
Average visibility in September
Nelson, 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).
Nelson, Illinois, USA
Weather forecast for your location
2. Allow the app to use your location