September weather forecast
Unity, IL

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Weather in September

The first month of the autumn, September, is also a moderately hot month in Unity, Illinois, with an average temperature ranging between min 61.9°F (16.6°C) and max 81.5°F (27.5°C).

Temperature

The shift to September signals an average high-temperature of a moderately hot 81.5°F (27.5°C), subtly varied from August's 86.4°F (30.2°C). Unity, during the month of September, experiences an average low-temperature of 61.9°F (16.6°C).

Heat index

The heat index value for September is calculated to be a hot 86°F (30°C). Long-standing exposure and activity could induce a feeling of tiredness and lead to heat cramps.
Heat index data is primarily for areas with shade and subjected to light winds. Direct sunshine exposure could raise heat index values by as much as 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'apparent temperature' or 'real feel', is a calculation that merges air temperature and relative humidity to depict the sensation of warmth. Elements such as metabolic variations, pregnancy, and physical exertion can influence one's weather perception. It is noteworthy that being in direct sunlight can enhance the weather's impact, raising the heat index by as much as 15 Fahrenheit (8 Celsius) degrees. Heat index values are extremely significant for babies and toddlers. Children are often less aware of the need to rest and re-hydrate. Thirst is a late sign of dehydration - it's vital to remain hydrated, particularly during prolonged physical activities.

Humidity

In September, the average relative humidity is 72%.

Rainfall

September is the month with the least rainfall. Rain falls for 11.4 days and accumulates 1.42" (36mm) of precipitation.

Snowfall

In Unity, snow does not fall in May through September.

Daylight

The average length of the day in September is 12h and 25min.
On the first day of the month, sunrise is at 6:28 am and sunset at 7:25 pm. On the last day of September, in Unity, sunrise is at 6:52 am and sunset at 6:41 pm CDT.

Sunshine

In September, the average sunshine is 9.6h.

UV index

In September, the average daily maximum UV index is 5. A UV Index estimate of 3 to 5 represents a moderate threat to health from unprotected exposure to Sun's UV rays for ordinary individuals.
Note: A daily maximum UV index of 5 in September translates into the following instructions:
Guard yourself - Avoiding sunburn is suggested. Direct exposure to the Sun's intense radiation around midday should be avoided for health reasons. Outfit yourself in sun-safe attire, like long sleeves, pants, a hat, and UV-blocking sunglasses.
Updated: Jul 22, 2024
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate

Frequently asked questions

What are the temperatures in September?

In September, the average high-temperature and low-temperature are 81.5°F (27.5°C) and 61.9°F (16.6°C) respectively. In September, the average heat index (a.k.a. 'real feel', 'feels like'), which takes the relative humidity and factors it into the air temperature reading, is calculated to be 86°F (30°C).

What is the average humidity in September?

The average relative humidity in September is 72%.

What is the driest month?

The month with the least rainfall is September, when the rain falls for 11.4 days and typically collects 1.42" (36mm) of precipitation.

How much does it rain in September?

In Unity, in September, it is raining for 11.4 days, with typically 1.42" (36mm) of accumulated precipitation.

When it does not snow?

May through September are months without snowfall.

Does it snow in September?

In Unity, in September, it doesn't snow. In October, it regularly snows.

What is the average length of the day in September?

In Unity, the average day length in September is 12h and 25min.

When is the sunrise / sunset in September in Unity?

On the first day of September in Unity, sunrise is at 6:28 am and sunset at 7:25 pm. On the last day of the month, sunrise is at 6:52 am and sunset at 6:41 pm CDT.

How many hours of sunshine does Unity have in September?

In September, the average sunshine duration is 9.6h.

What is the UV index intensity in September?

In September, the average daily maximum UV index is 5. A UV Index estimate of 3 to 5 represents a moderate vulnerability from unprotected exposure to UV radiation.
Average humidity
Average rainfall days
Average snowfall
Average snowfall days
Average daylight
Average sunshine
Average sunshine days
Average UV index
Average cloud cover
Average visibility

Average temperature in September
Unity, IL

Average temperature in September - Unity, IL
  • Average high temperature in September: 81.5°F

The warmest month (with the highest average high temperature) is July (88.2°F).
The month with the lowest average high temperature is January (41.2°F).

  • Average low temperature in September: 61.9°F

The month with the highest average low temperature is July (69.8°F).
The coldest month (with the lowest average low temperature) is January (28.4°F).

Average pressure in September
Unity, IL

Average pressure in September - Unity, IL
  • Average pressure in September: 30.02"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
Unity, IL

Average wind speed in September - Unity, IL
  • Average wind speed in September: 6.3mph

The windiest months (with the highest average wind speed) are January, February and March (9.1mph).
The calmest months (with the lowest average wind speed) are July and August (5.7mph).

Average humidity in September
Unity, IL

Average humidity in September - Unity, IL
  • Average humidity in September: 72%

The months with the highest relative humidity are February, March, May and December (78%).
The month with the lowest relative humidity is October (69%).

Average rainfall in September
Unity, IL

Average rainfall in September - Unity, IL
  • Average rainfall in September: 1.42"

The wettest month (with the highest rainfall) is April (4.21").
The driest month (with the least rainfall) is September (1.42").

Average rainfall days in September
Unity, IL

Average rainfall days in September - Unity, IL
  • Average rainfall days in September: 11.4 days

The month with the highest number of rainy days is May (17.1 days).
The month with the least rainy days is January (9.8 days).

Average snowfall in September
Unity, IL

Average snowfall in September - Unity, IL
  • Average snowfall in September: 0"

The month with the highest snowfall is February (1.5").
The months with the least snowfall are May, June, July, August and September (0").

Average snowfall days in September
Unity, IL

Average snowfall days in September - Unity, IL
  • Average snowfall days in September: 0 days

The month with the highest number of snowfall days is February (3.8 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
Unity, IL

Average daylight in September / Average sunshine in September - Unity, 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 42min).

  • Average sunshine in September: 9h and 4min

The month with the most sunshine is June (Average sunshine: 10h and 42min).
The month with the least sunshine is February (Average sunshine: 4h and 42min).

Average sunshine days in September
Unity, IL

Average sunshine days in September - Unity, IL
  • Average sunshine days in September: 16.5 days

The month with the most sunshine days is October (18.5 days).
The month with the least sunshine days is May (12.3 days).

Average UV index in September
Unity, IL

Average UV index in September - Unity, 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
Unity, IL

Average cloud cover in September - Unity, IL
  • Average cloud cover in September: 27

The month with the most cloud cover is February (Cloud cover 49).
The month with the least cloud cover is June (Cloud cover 26).

Average visibility in September
Unity, IL

Average visibility in September - Unity, 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).

Unity, Illinois, USA

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