August weather forecast
Forreston, IL

Share

Weather in August

August, the last month of the summer in Forreston, is also a moderately hot month, with an average temperature ranging between max 78.4°F (25.8°C) and min 61°F (16.1°C).

Temperature

Forreston, Illinois, records a slight change with August's average high-temperatures adjusting to a still warm 78.4°F (25.8°C) from July's 79.7°F (26.5°C). August is noted for a mean low-temperature of 61°F (16.1°C).

Humidity

In August, the average relative humidity in Forreston is 84%.

Rainfall

In Forreston, Illinois, in August, during 15.3 rainfall days, 2.01" (51mm) of precipitation is typically accumulated. In Forreston, during the entire year, the rain falls for 145.6 days and collects up to 23.43" (595mm) of precipitation.

Snowfall

May through September are months without snowfall.

Daylight

In Forreston, the average length of the day in August is 13h and 50min.
On the first day of the month, sunrise is at 5:52 am and sunset at 8:16 pm. On the last day of August, sunrise is at 6:23 am and sunset at 7:33 pm CDT.

Sunshine

The average sunshine in August in Forreston is 9.5h.

UV index

The months with the highest UV index in Forreston are May through August, with an average maximum UV index of 5. A UV Index value of 3 to 5 symbolizes a moderate threat to health from exposure to the Sun's UV radiation for the average person.
Note: The daily high UV index of 5 in August translates into this advice:
Put precautions into practice - Protective measures against sun-induced damage are advised. The best time to avoid the Sun's harmful UV radiation is during midday when it's most potent. Limit sun-induced ocular harm with sunglasses that feature UVA and UVB filtration.
Updated: Feb 12, 2024
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate

Frequently asked questions

What is the temperature in August in Forreston?

In Forreston, 78.4°F (25.8°C) is the average high-temperature and 61°F (16.1°C) is the average low-temperature during August.

What is the average humidity in August in Forreston?

In August, the average relative humidity in Forreston, Illinois, is 84%.

How many days does it rain in August in Forreston?

In Forreston, Illinois, during August, the rain falls for 15.3 days and regularly aggregates up to 2.01" (51mm) of precipitation.

When it does not snow in Forreston?

In Forreston, Illinois, snow does not fall in May through September.

What is the average length of the day in August in Forreston?

In Forreston, Illinois, the average day length in August is 13h and 50min.

When is the sunrise / sunset in August in Forreston?

On the first day of August in Forreston, Illinois, sunrise is at 5:52 am and sunset at 8:16 pm. On the last day of the month, sunrise is at 6:23 am and sunset at 7:33 pm CDT.

How many hours of sunshine does Forreston have in August?

In Forreston, Illinois, the average sunshine duration in August is 9.5h.

What are the months with the highest UV index in Forreston?

The months with the highest UV index are May through August, with an average maximum UV index of 5.

What is the UV index intensity in August in Forreston?

In August, the average daily maximum UV index in Forreston, Illinois, is 5. A UV Index estimate of 3 to 5 represents a moderate vulnerability from exposure to the Sun's 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 August
Forreston, IL

Average temperature in August - Forreston, IL
  • Average high temperature in August: 78.4°F

The warmest month (with the highest average high temperature) is July (79.7°F).
The month with the lowest average high temperature is January (26.1°F).

  • Average low temperature in August: 61°F

The month with the highest average low temperature is July (63.5°F).
The coldest month (with the lowest average low temperature) is January (13.5°F).

Average pressure in August
Forreston, IL

Average pressure in August - Forreston, IL
  • Average pressure in August: 29.97"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 August
Forreston, IL

Average wind speed in August - Forreston, IL
  • Average wind speed in August: 6.5mph

The windiest month (with the highest average wind speed) is April (10.3mph).
The calmest month (with the lowest average wind speed) is August (6.5mph).

Average humidity in August
Forreston, IL

Average humidity in August - Forreston, IL
  • Average humidity in August: 84%

The month with the highest relative humidity is January (87%).
The months with the lowest relative humidity are April and October (75%).

Average rainfall in August
Forreston, IL

Average rainfall in August - Forreston, IL
  • Average rainfall in August: 2.01"

The wettest month (with the highest rainfall) is June (3.39").
The driest months (with the least rainfall) are February and December (1.06").

Average rainfall days in August
Forreston, IL

Average rainfall days in August - Forreston, IL
  • Average rainfall days in August: 15.3 days

The month with the highest number of rainy days is May (18.3 days).
The month with the least rainy days is February (5 days).

Average snowfall in August
Forreston, IL

Average snowfall in August - Forreston, IL
  • Average snowfall in August: 0"

The month with the highest snowfall is January (3.54").
The months with the least snowfall are May, June, July, August and September (0").

Average snowfall days in August
Forreston, IL

Average snowfall days in August - Forreston, IL
  • Average snowfall days in August: 0 days

The month with the highest number of snowfall days is January (12.4 days).
The months with the least snowfall days are May, June, July, August and September (0 days).

Average daylight in August /
Average sunshine in August
Forreston, IL

Average daylight in August / Average sunshine in August - Forreston, IL
  • Average daylight in August: 13h and 5min

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 August: 9h and 3min

The month with the most sunshine is July (Average sunshine: 9h and 42min).
The month with the least sunshine is January (Average sunshine: 3h and 36min).

Average sunshine days in August
Forreston, IL

Average sunshine days in August - Forreston, IL
  • Average sunshine days in August: 12.9 days

The month with the most sunshine days is November (17.2 days).
The month with the least sunshine days is June (9.7 days).

Average UV index in August
Forreston, IL

Average UV index in August - Forreston, IL
  • Average UV index in August: 5

The months with the highest UV index are May, June, July and August (UV index 5).
The months with the lowest UV index are January and December (UV index 1).

Average cloud cover in August
Forreston, IL

Average cloud cover in August - Forreston, IL
  • Average cloud cover in August: 34

The month with the most cloud cover is January (Cloud cover 62).
The month with the least cloud cover is September (Cloud cover 33).

Average visibility in August
Forreston, IL

Average visibility in August - Forreston, IL
  • Average visibility in August: 5mi

The months with the highest visibility are March, April, May, June, September, October, November and December (6mi).
The months with the lowest visibility are January, February, July and August (5mi).

Forreston, Illinois, USA

Weather forecast for your location

1. Click Locate me button
2. Allow the app to use your location