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 move into September indicates a slight reduction in the average high-temperature, down from August's tropical 86.5°F (30.3°C) to a moderately hot 81.1°F (27.3°C). Grantsburg observes an average low-temperature of 60.6°F (15.9°C) during September nights.Heat index
September's heat index is estimated at a hot 86°F (30°C). Constant exposure and activity lead to possible fatigue. Prolonged exercise may result in heat cramps.Heat index data is primarily for areas with shade and subjected to light winds. Direct sunlight exposure may result in a rise of the heat index by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'feels like' or 'real feel', is derived by integrating air temperature with the existing relative humidity to express the perceived warmth. Additional elements including metabolic differences, the level of physical activity, and attire have a role in shaping the individual's temperature perception. When directly under the sun, the weather's impact can intensify, possibly boosting the heat index by 15 Fahrenheit (8 Celsius) degrees. Heat index values are of high significance for children. Children usually face more risks than adults as their ability to sweat is less. Additionally, their larger skin surface in relation to their petite bodies and higher heat output due to their activities increases their vulnerability.
Humidity
In Grantsburg, Illinois, the average relative humidity in September is 73%.Rainfall
The month with the least rainfall is September, when the rain falls for 8.3 days and typically collects 0.47" (12mm) of precipitation.Snowfall
April through October are months without snowfall.Daylight
The average length of the day in September is 12h and 25min.On the first day of September, sunrise is at 6:26 am and sunset at 7:23 pm. On the last day of the month, sunrise is at 6:50 am and sunset at 6:39 pm CDT.
Sunshine
In Grantsburg, the average sunshine in September is 9.4h.UV index
The average daily maximum UV index in September is 5. A UV Index estimate of 3 to 5 represents a medium health hazard from unsafe exposure to UV radiation for average individuals.Note: The daily high UV index of 5 during September translates into the following recommendations:
Guard yourself - Precautionary measures against sun damage are advocated. The best time to avoid the Sun's harmful UV radiation is during midday when it's most potent. Always opt for UVA and UVB-resistant sunglasses on radiant days.
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?
What is the driest month?
How much does it rain in September?
When it does not snow?
How many hours of daylight does Grantsburg have in September?
When is the sunrise / sunset in September?
How long on average sun shines in September?
How high is the UV index in September?
Average temperature in September
Grantsburg, IL
- Average high temperature in September: 81.1°F
The warmest month (with the highest average high temperature) is July (88°F).
The month with the lowest average high temperature is January (40.1°F).
- Average low temperature in September: 60.6°F
The month with the highest average low temperature is July (68.5°F).
The coldest month (with the lowest average low temperature) is January (27°F).
Average pressure in September
Grantsburg, IL
- Average pressure in September: 30.03"Hg
The month with the highest atmospheric pressure is January (30.16"Hg).
The month with the lowest atmospheric pressure is June (29.94"Hg).
Average wind speed in September
Grantsburg, IL
- Average wind speed in September: 6.3mph
The windiest months (with the highest average wind speed) are January and February (9mph).
The calmest months (with the lowest average wind speed) are July and August (5.7mph).
Average humidity in September
Grantsburg, IL
- Average humidity in September: 73%
The months with the highest relative humidity are March and May (79%).
The month with the lowest relative humidity is October (71%).
Average rainfall in September
Grantsburg, IL
- Average rainfall in September: 0.47"
The wettest month (with the highest rainfall) is June (1.5").
The driest month (with the least rainfall) is September (0.47").
Average rainfall days in September
Grantsburg, IL
- Average rainfall days in September: 8.3 days
The month with the highest number of rainy days is July (13.1 days).
The months with the least rainy days are January, February and December (7.3 days).
Average snowfall in September
Grantsburg, IL
- Average snowfall in September: 0"
The month with the highest snowfall is February (0.67").
The months with the least snowfall are April, May, June, July, August, September and October (0").
Average snowfall days in September
Grantsburg, IL
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (3.3 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
Grantsburg, IL
- Average daylight in September: 12h and 2min
The month with the longest days is June (Average daylight: 14h and 42min).
The month with the shortest days is December (Average daylight: 9h and 36min).
- Average sunshine in September: 9h and 2min
The months with the most sunshine are June and July (Average sunshine: 10h and 24min).
The months with the least sunshine are January and February (Average sunshine: 4h and 36min).
Average sunshine days in September
Grantsburg, IL
- Average sunshine days in September: 19.1 days
The month with the most sunshine days is October (21.5 days).
The month with the least sunshine days is June (14.8 days).
Average UV index in September
Grantsburg, IL
- Average UV index in September: 5
The months with the highest UV index are May, June, July and August (UV index 6).
The months with the lowest UV index are January, February and December (UV index 2).
Average cloud cover in September
Grantsburg, IL
- Average cloud cover in September: 28
The months with the most cloud cover are January and February (Cloud cover 51).
The month with the least cloud cover is September (Cloud cover 28).
Average visibility in September
Grantsburg, 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).
Grantsburg, Illinois, USA
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