Climate and monthly weather forecastForrest, IL
Climate and monthly weather forecast
Weather in January
January, the same as December, in Forrest, Illinois, is another subzero cold winter month, with an average temperature ranging between min 18.5°F (-7.5°C) and max 30.6°F (-0.8°C). January, noted for its average high-temperature of 30.6°F (-0.8°C) and an average low-temperature of 18.5°F (-7.5°C), is considered the coldest month. Weather in January »Weather in February
February, the last month of the winter in Forrest, is a cold month, with an average temperature fluctuating between 21.7°F (-5.7°C) and 35.1°F (1.7°C). Forrest's February showcases an average high-temperature of a cold 35.1°F (1.7°C), hardly distinct from January's 30.6°F (-0.8°C). Weather in February »Weather in March
The first month of the spring, March, is a chilly month in Forrest, Illinois, with an average temperature varying between 33.4°F (0.8°C) and 47.7°F (8.7°C). Forrest's transition into March is marked by a temperature shift, moving from a cold 35.1°F (1.7°C) in February to a frosty 47.7°F (8.7°C). Weather in March »Weather in April
April in Forrest, Illinois, is a refreshing spring month, with an average temperature fluctuating between 59.7°F (15.4°C) and 43.9°F (6.6°C). The rise of average high-temperatures is seen in April, with an increase from a chilly 47.7°F (8.7°C) in March to a refreshing 59.7°F (15.4°C). Weather in April »Weather in May
The last month of the spring, May, is a pleasant month in Forrest, Illinois, with an average temperature varying between 71.6°F (22°C) and 55°F (12.8°C). The shift into May is accompanied by a temperature increase, with the average high-temperature rising from a moderate 59.7°F (15.4°C) in April to an agreeable 71.6°F (22°C). Weather in May »Weather in June
The first month of the summer, June, is a warm month in Forrest, Illinois, with an average temperature ranging between min 62.8°F (17.1°C) and max 79.3°F (26.3°C). As May transitions into June, a subtle temperature shift is observed, with average highs adjusting from a pleasant 71.6°F (22°C) to a warm 79.3°F (26.3°C). Weather in June »Weather in July
July, like June, in Forrest, Illinois, is another warm summer month, with an average temperature fluctuating between 64.6°F (18.1°C) and 80.8°F (27.1°C). July, recording an average high temperature of 80.8°F (27.1°C) and a low temperature of 64.6°F (18.1°C), is Forrest's warmest month. The heat index for July is computed to be a hot 87.8°F (31°C). Weather in July »Weather in August
August, the last month of the summer in Forrest, is also a moderately hot month, with temperature in the range of an average high of 79.7°F (26.5°C) and an average low of 62.6°F (17°C). Forrest's average high-temperature marks a still warm 79.7°F (26.5°C) with the advent of August, closely mirroring that of the preceding month. Weather in August »Weather in September
September, the first month of the autumn in Forrest, is still a warm month, with temperature in the range of an average high of 75.7°F (24.3°C) and an average low of 57.2°F (14°C). September's arrival brings an average high-temperature of a still moderately hot 75.7°F (24.3°C), slightly deviating from August's 79.7°F (26.5°C). Weather in September »Weather in October
October, like September, in Forrest, Illinois, is another enjoyable autumn month, with temperature in the range of an average high of 62.2°F (16.8°C) and an average low of 46.8°F (8.2°C). The arrival of October corresponds with a temperature reduction, down from September's moderately hot 75.7°F (24.3°C) to a refreshing 62.2°F (16.8°C). Weather in October »Weather in November
November, the last month of the autumn in Forrest, is also a frosty month, with an average temperature fluctuating between 34.9°F (1.6°C) and 47.8°F (8.8°C). The shift into November brings a noticeable decrease in the average high-temperature, falling from a refreshing 62.2°F (16.8°C) in October to a frosty 47.8°F (8.8°C). Weather in November »Weather in December
December, the first month of the winter in Forrest, is still a cold month, with an average temperature varying between 26.1°F (-3.3°C) and 36.5°F (2.5°C). As December commences, the average high-temperature shows a reduction, transitioning from a frosty 47.8°F (8.8°C) in November to an icy 36.5°F (2.5°C). Weather in December »Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature
Forrest, IL
The warmest month (with the highest average high temperature) is July (80.8°F).
The month with the lowest average high temperature is January (30.6°F).
The month with the highest average low temperature is July (64.6°F).
The coldest month (with the lowest average low temperature) is January (18.5°F).
Average pressure
Forrest, IL
- Average pressure in January:
30.13"Hg - Average pressure in February:
30.11"Hg - Average pressure in March:
30.08"Hg - Average pressure in April:
29.94"Hg - Average pressure in May:
29.96"Hg - Average pressure in June:
29.92"Hg
- Average pressure in July:
29.97"Hg - Average pressure in August:
29.98"Hg - Average pressure in September:
30.03"Hg - Average pressure in October:
30.02"Hg - Average pressure in November:
30.11"Hg - Average pressure in December:
30.11"Hg
The month with the highest atmospheric pressure is January (30.13"Hg).
The month with the lowest atmospheric pressure is June (29.92"Hg).
Average wind speed
Forrest, IL
- Average wind speed in January:
10.8mph - Average wind speed in February:
10.6mph - Average wind speed in March:
10.3mph - Average wind speed in April:
10.6mph - Average wind speed in May:
9.1mph - Average wind speed in June:
7.9mph
- Average wind speed in July:
6.5mph - Average wind speed in August:
6.4mph - Average wind speed in September:
7.6mph - Average wind speed in October:
9.5mph - Average wind speed in November:
10.3mph - Average wind speed in December:
10.2mph
The windiest month (with the highest average wind speed) is January (10.8mph).
The calmest month (with the lowest average wind speed) is August (6.4mph).
Average humidity
Forrest, IL
The month with the highest relative humidity is July (86%).
The month with the lowest relative humidity is October (71%).
Average rainfall
Forrest, IL
- Average rainfall in January:
0.79" - Average rainfall in February:
0.87" - Average rainfall in March:
1.34" - Average rainfall in April:
1.97" - Average rainfall in May:
2.56" - Average rainfall in June:
2.05"
- Average rainfall in July:
2.09" - Average rainfall in August:
1.5" - Average rainfall in September:
1.18" - Average rainfall in October:
1.34" - Average rainfall in November:
0.91" - Average rainfall in December:
0.87"
The wettest month (with the highest rainfall) is May (2.56").
The driest month (with the least rainfall) is January (0.79").
Average rainfall days
Forrest, IL
- Average rainfall days in January:
5 days - Average rainfall days in February:
5 days - Average rainfall days in March:
11.2 days - Average rainfall days in April:
13.3 days - Average rainfall days in May:
17 days - Average rainfall days in June:
15.1 days
- Average rainfall days in July:
15.3 days - Average rainfall days in August:
13.3 days - Average rainfall days in September:
10.5 days - Average rainfall days in October:
10.3 days - Average rainfall days in November:
7.6 days - Average rainfall days in December:
6.9 days
The month with the highest number of rainy days is May (17 days).
The months with the least rainy days are January and February (5 days).
Average snowfall
Forrest, IL
The month with the highest snowfall is January (2.09").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days
Forrest, IL
- Average snowfall days in January:
10.6 days - Average snowfall days in February:
7.1 days - Average snowfall days in March:
3.7 days - Average snowfall days in April:
0.8 days - Average snowfall days in May:
0 days - Average snowfall days in June:
0 days
- Average snowfall days in July:
0 days - Average snowfall days in August:
0 days - Average snowfall days in September:
0 days - Average snowfall days in October:
0.2 days - Average snowfall days in November:
2 days - Average snowfall days in December:
6.1 days
The month with the highest number of snowfall days is January (10.6 days).
The months with the least snowfall days are May, June, July, August and September (0 days).
Average daylight / Average sunshine
Forrest, IL
- Average daylight in January:
9h and 36min - Average daylight in February:
10h and 42min - Average daylight in March:
12h and 0min - Average daylight in April:
13h and 18min - Average daylight in May:
14h and 30min - Average daylight in June:
15h and 0min
- Average daylight in July:
14h and 48min - Average daylight in August:
13h and 42min - Average daylight in September:
12h and 30min - Average daylight in October:
11h and 6min - Average daylight in November:
9h and 54min - Average daylight in December:
9h and 18min
The month with the longest days is June (Average daylight: 15h and 0min).
The month with the shortest days is December (Average daylight: 9h and 18min).
- Average sunshine in January:
3h and 48min - Average sunshine in February:
4h and 6min - Average sunshine in March:
6h and 12min - Average sunshine in April:
7h and 48min - Average sunshine in May:
8h and 48min - Average sunshine in June:
9h and 54min
- Average sunshine in July:
9h and 36min - Average sunshine in August:
9h and 48min - Average sunshine in September:
8h and 54min - Average sunshine in October:
5h and 54min - Average sunshine in November:
5h and 6min - Average sunshine in December:
4h and 18min
The month with the most sunshine is June (Average sunshine: 9h and 54min).
The month with the least sunshine is January (Average sunshine: 3h and 48min).
Average sunshine days
Forrest, IL
- Average sunshine days in January:
17.2 days - Average sunshine days in February:
16.8 days - Average sunshine days in March:
16.3 days - Average sunshine days in April:
14.5 days - Average sunshine days in May:
11.5 days - Average sunshine days in June:
12.2 days
- Average sunshine days in July:
11.4 days - Average sunshine days in August:
13.5 days - Average sunshine days in September:
17.2 days - Average sunshine days in October:
19.1 days - Average sunshine days in November:
19.5 days - Average sunshine days in December:
18.9 days
The month with the most sunshine days is November (19.5 days).
The month with the least sunshine days is July (11.4 days).
Average UV index
Forrest, IL
The months with the highest UV index are June and July (UV index 6).
The month with the lowest UV index is December (UV index 1).
Average cloud cover
Forrest, IL
The month with the most cloud cover is January (Cloud cover 59).
The month with the least cloud cover is September (Cloud cover 32).
Average visibility
Forrest, IL
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).





