Climate and monthly weather forecastOswego, IL
Climate and monthly weather forecast
Weather in January
January, the same as December, in Oswego, Illinois, is another subzero cold winter month, with an average temperature ranging between min 16.7°F (-8.5°C) and max 28.4°F (-2°C). Oswego's January weather, with an average high temperature of 28.4°F (-2°C) and an average low temperature of 16.7°F (-8.5°C), tends to be the coldest of the year. Weather in January »Weather in February
The last month of the winter, February, is a wintry month in Oswego, Illinois, with temperature in the range of an average low of 19.8°F (-6.8°C) and an average high of 32.5°F (0.3°C). Oswego notes an average high-temperature of a cold 32.5°F (0.3°C) in February, hardly diverging from January. Weather in February »Weather in March
March, the first month of the spring in Oswego, is a chilly month, with an average temperature ranging between max 45.7°F (7.6°C) and min 31.5°F (-0.3°C). Oswego's transition into March is marked by a temperature shift, moving from a cold 32.5°F (0.3°C) in February to a chilly 45.7°F (7.6°C). Weather in March »Weather in April
April in Oswego, Illinois, is a refreshing spring month, with temperature in the range of an average high of 57°F (13.9°C) and an average low of 40.8°F (4.9°C). As March transitions into April, Oswego sees a rise in the average high-temperature, moving from a frosty 45.7°F (7.6°C) to a moderate 57°F (13.9°C). Weather in April »Weather in May
The last month of the spring, May, is a pleasant month in Oswego, Illinois, with an average temperature ranging between min 52.3°F (11.3°C) and max 69.4°F (20.8°C). The arrival of May brings a temperature shift, with the average high-temperature escalating from a mild 57°F (13.9°C) in April to a pleasant 69.4°F (20.8°C). Weather in May »Weather in June
The first month of the summer, June, is a moderately hot month in Oswego, Illinois, with an average temperature ranging between max 78.4°F (25.8°C) and min 60.8°F (16°C). June indicates a change in the average high-temperature, moving up from a pleasant 69.4°F (20.8°C) in May to a moderately hot 78.4°F (25.8°C). Weather in June »Weather in July
July, the same as June, is a moderately hot summer month in Oswego, Illinois, with an average temperature varying between 64.2°F (17.9°C) and 81.1°F (27.3°C). July, known for its average high temperature of 81.1°F (27.3°C) and an average low temperature of 64.2°F (17.9°C), is the warmest month. The heat index for July is estimated at a hot 87.8°F (31°C). Weather in July »Weather in August
August, the last month of the summer in Oswego, is also a moderately hot month, with temperature in the range of an average low of 62.4°F (16.9°C) and an average high of 79.3°F (26.3°C). Oswego notes an average high-temperature of a still warm 79.3°F (26.3°C) in August, displaying minor variation from July. Weather in August »Weather in September
The first month of the autumn, September, is still a warm month in Oswego, Illinois, with temperature in the range of an average high of 74.1°F (23.4°C) and an average low of 56.3°F (13.5°C). The average high-temperature in September, at a still moderately hot 74.1°F (23.4°C), reveals a modest deviation from August's 79.3°F (26.3°C). Weather in September »Weather in October
October, the same as September, is another refreshing autumn month in Oswego, Illinois, with an average temperature varying between 60.8°F (16°C) and 45.1°F (7.3°C). Oswego in October undergoes a mild reduction in the average high-temperature, shifting from September's moderately hot 74.1°F (23.4°C) to a refreshing 60.8°F (16°C). Weather in October »Weather in November
November, the last month of the autumn in Oswego, is also a frosty month, with an average temperature fluctuating between 46°F (7.8°C) and 33.3°F (0.7°C). Witnessing a clear downswing, the average high-temperature during November drops from October's enjoyable 60.8°F (16°C) to a frosty 46°F (7.8°C). Weather in November »Weather in December
The first month of the winter, December, is also an icy month in Oswego, Illinois, with an average temperature varying between 24.1°F (-4.4°C) and 34.5°F (1.4°C). The beginning of December involves a decrease in the average high-temperature, transitioning from a frosty 46°F (7.8°C) in November to an icy 34.5°F (1.4°C). Weather in December »Updated: Feb 12, 2024
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
During the coldest month in Oswego, January, temperatures average a high of 28.4°F (-2°C) and a low of 16.7°F (-8.5°C).
The months with the highest humidity in Oswego are January, February, July and August, with an average relative humidity of 83%.
In Oswego, Illinois, during the entire year, the rain falls for 133.1 days and collects up to 16.93" (430mm) of precipitation.
Months with snowfall are January through April, October through December.
The month with the most snowfall in Oswego is January, when snow falls for 10.7 days and typically aggregates up to 1.73" (44mm) of snow.
Throughout the year, in Oswego, Illinois, there are 39.5 snowfall days, and 6.69" (170mm) of snow is accumulated.
January has the least sunshine of the year in Oswego, with an average of 3.8h of sunshine.
The months with the lowest UV index are January and December, with an average maximum UV index of 1.
On Sunday, March 10. 2024, at 2:00 am, Daylight Saving Time starts in Oswego, Illinois, and the time zone changes from CST to CDT. Daylight Saving Time ends Sunday, November 3. 2024, at 2:00 am, and the time zone reverts from CDT to CST.
May through September are months without snowfall.
The month with the most rainfall in Oswego, Illinois, is June, when the rain falls for 14.9 days and typically aggregates up to 2.24" (57mm) of precipitation.
With an average of 15h and 12min of daylight, June has the longest days of the year.
June and July, with an average maximum UV index of 6, are months with the highest UV index in Oswego.
Oswego's temperatures tend to reach their peak averages in July, with a high of 81.1°F (27.3°C) and a low of 64.2°F (17.9°C).
The month with the most sunshine in Oswego, Illinois, is July, with an average of 9.8h of sunshine.
With an average relative humidity of 74%, October is the least humid month in Oswego.
November and December are months with the least rain when the rain falls for 7.6 days and typically aggregates up to 0.75" (19mm) of rain.
With an average of 9h and 12min of daylight, December has the shortest days of the year in Oswego.
Average temperature
Oswego, IL
The warmest month (with the highest average high temperature) is July (81.1°F).
The month with the lowest average high temperature is January (28.4°F).
The month with the highest average low temperature is July (64.2°F).
The coldest month (with the lowest average low temperature) is January (16.7°F).
Average pressure
Oswego, IL
- Average pressure in January:
30.11"Hg - Average pressure in February:
30.1"Hg - Average pressure in March:
30.09"Hg - Average pressure in April:
29.95"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:
30.01"Hg - Average pressure in November:
30.1"Hg - Average pressure in December:
30.1"Hg
The month with the highest atmospheric pressure is January (30.11"Hg).
The month with the lowest atmospheric pressure is June (29.92"Hg).
Average wind speed
Oswego, IL
- Average wind speed in January:
9.6mph - Average wind speed in February:
9.6mph - Average wind speed in March:
9.4mph - Average wind speed in April:
9.7mph - Average wind speed in May:
8.2mph - Average wind speed in June:
7.1mph
The windiest month (with the highest average wind speed) is April (9.7mph).
The calmest month (with the lowest average wind speed) is August (6mph).
Average humidity
Oswego, IL
The months with the highest relative humidity are January, February, July and August (83%).
The month with the lowest relative humidity is October (74%).
Average rainfall
Oswego, IL
- Average rainfall in January:
0.87" - Average rainfall in February:
0.79" - Average rainfall in March:
0.94" - Average rainfall in April:
1.77" - Average rainfall in May:
2.13" - Average rainfall in June:
2.24"
- Average rainfall in July:
2.17" - Average rainfall in August:
1.77" - Average rainfall in September:
1.3" - Average rainfall in October:
1.46" - Average rainfall in November:
0.75" - Average rainfall in December:
0.75"
The wettest month (with the highest rainfall) is June (2.24").
The driest months (with the least rainfall) are November and December (0.75").
Average rainfall days
Oswego, IL
- Average rainfall days in January:
5 days - Average rainfall days in February:
4.3 days - Average rainfall days in March:
10.3 days - Average rainfall days in April:
14.4 days - Average rainfall days in May:
15.3 days - Average rainfall days in June:
14.9 days
- Average rainfall days in July:
16.6 days - Average rainfall days in August:
15 days - Average rainfall days in September:
12 days - Average rainfall days in October:
11.2 days - Average rainfall days in November:
7.6 days - Average rainfall days in December:
6.5 days
The month with the highest number of rainy days is July (16.6 days).
The month with the least rainy days is February (4.3 days).
Average snowfall
Oswego, IL
The month with the highest snowfall is January (1.73").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days
Oswego, IL
- Average snowfall days in January:
10.7 days - Average snowfall days in February:
9.3 days - Average snowfall days in March:
5.6 days - Average snowfall days in April:
1.8 days - Average snowfall days in May:
0.1 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:
0.4 days - Average snowfall days in November:
2.8 days - Average snowfall days in December:
8.8 days
The month with the highest number of snowfall days is January (10.7 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight / Average sunshine
Oswego, IL
- Average daylight in January:
9h and 36min - Average daylight in February:
10h and 36min - Average daylight in March:
12h and 0min - Average daylight in April:
13h and 24min - Average daylight in May:
14h and 36min - Average daylight in June:
15h and 12min
- Average daylight in July:
14h and 48min - Average daylight in August:
13h and 48min - Average daylight in September:
12h and 30min - Average daylight in October:
11h and 6min - Average daylight in November:
9h and 48min - Average daylight in December:
9h and 12min
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 January:
3h and 48min - Average sunshine in February:
4h and 0min - Average sunshine in March:
6h and 12min - Average sunshine in April:
7h and 42min - Average sunshine in May:
8h and 42min - Average sunshine in June:
9h and 42min
- Average sunshine in July:
9h and 48min - Average sunshine in August:
9h and 42min - Average sunshine in September:
8h and 42min - Average sunshine in October:
5h and 42min - Average sunshine in November:
5h and 12min - Average sunshine in December:
4h and 12min
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
Oswego, IL
- Average sunshine days in January:
17 days - Average sunshine days in February:
15.4 days - Average sunshine days in March:
15.7 days - Average sunshine days in April:
12.3 days - Average sunshine days in May:
12.5 days - Average sunshine days in June:
11.8 days
- Average sunshine days in July:
10.2 days - Average sunshine days in August:
11.6 days - Average sunshine days in September:
14.5 days - Average sunshine days in October:
17.6 days - Average sunshine days in November:
19.5 days - Average sunshine days in December:
17.7 days
The month with the most sunshine days is November (19.5 days).
The month with the least sunshine days is July (10.2 days).
Average UV index
Oswego, IL
The months with the highest UV index are June and July (UV index 6).
The months with the lowest UV index are January and December (UV index 1).
Average cloud cover
Oswego, IL
The month with the most cloud cover is January (Cloud cover 60).
The month with the least cloud cover is September (Cloud cover 32).
Average visibility
Oswego, 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).
