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Contents
- Weather in January
- Weather in February
- Weather in March
- Weather in April
- Weather in May
- Weather in June
- Weather in July
- Weather in August
- Weather in September
- Weather in October
- Weather in November
- Weather in December
- Frequently asked questions
- Average temperature
- Average pressure
- Average wind speed
- Average humidity
- Average rainfall
- Average rainfall days
- Average snowfall
- Average snowfall days
- Average daylight
- Average sunshine
- Average sunshine days
- Average UV index
- Average cloud cover
- Average visibility
Weather in January
January, like December, is a freezing cold winter month in Port Byron, Illinois, with an average temperature fluctuating between 15.4°F (-9.2°C) and 28.2°F (-2.1°C). January, with average temperatures reaching a high of 28.2°F (-2.1°C) and a low of 15.4°F (-9.2°C), is the coldest month. Weather in January »
Weather in February
February, the last month of the winter in Port Byron, is an icy month, with temperature in the range of an average high of 32.7°F (0.4°C) and an average low of 19.6°F (-6.9°C). The commencement of February notes an average high-temperature of a cold 32.7°F (0.4°C), exhibiting little difference from the previous month. Weather in February »
Weather in March
The first month of the spring, March, is a chilly month in Port Byron, Illinois, with temperature in the range of an average high of 46.8°F (8.2°C) and an average low of 32°F (0°C). March sees a rise in the average high-temperature, climbing from an icy 32.7°F (0.4°C) in February to a chilly 46.8°F (8.2°C). Weather in March »
Weather in April
April in Port Byron, Illinois, is a mild spring month, with an average temperature varying between 42.4°F (5.8°C) and 59°F (15°C). Port Byron's transition into April is marked by a temperature shift, moving from a chilly 46.8°F (8.2°C) in March to a mild 59°F (15°C). Weather in April »
Weather in May
May, the last month of the spring in Port Byron, is an agreeable month, with temperature in the range of an average low of 53.4°F (11.9°C) and an average high of 70.3°F (21.3°C). The onset of May marks an increase in the average high-temperature, moving from a mild 59°F (15°C) in April to a pleasant 70.3°F (21.3°C). Weather in May »
Weather in June
June, the first month of the summer in Port Byron, is a moderately hot month, with temperature in the range of an average low of 61.9°F (16.6°C) and an average high of 79°F (26.1°C). Entering June, Port Byron notices a subtle temperature elevation, with the average high-temperature advancing from May's agreeable 70.3°F (21.3°C) to a moderately hot 79°F (26.1°C). Weather in June »
Weather in July
July, like June, in Port Byron, Illinois, is another warm summer month, with an average temperature fluctuating between 64.8°F (18.2°C) and 81.7°F (27.6°C). In Port Byron, July is identified by the highest average temperatures, reaching a peak of 81.7°F (27.6°C) and a low of 64.8°F (18.2°C). July's mean heat index is evaluated at a tropical 89.6°F (32°C). Weather in July »
Weather in August
August, the last month of the summer in Port Byron, is another warm month, with an average temperature ranging between min 62.4°F (16.9°C) and max 80.6°F (27°C). The transition into August marks the average high-temperature at a still warm 80.6°F (27°C), differing minimally from July's 81.7°F (27.6°C). Weather in August »
Weather in September
September, the first month of the autumn in Port Byron, is also a moderately hot month, with temperature in the range of an average high of 75.4°F (24.1°C) and an average low of 56.3°F (13.5°C). With the onset of September, Port Byron's average high-temperature clocks in at a still moderately hot 75.4°F (24.1°C), showing a minor fluctuation from the previous month. Weather in September »
Weather in October
October, the same as September, is another enjoyable autumn month in Port Byron, Illinois, with temperature in the range of an average low of 45°F (7.2°C) and an average high of 61.3°F (16.3°C). October suggests a modest reduction in the average high-temperature, shifting from a moderately hot 75.4°F (24.1°C) in September to an enjoyable 61.3°F (16.3°C). Weather in October »
Weather in November
The last month of the autumn, November, is also a frosty month in Port Byron, Illinois, with temperature in the range of an average high of 46.9°F (8.3°C) and an average low of 33.3°F (0.7°C). Port Byron's weather in November is marked by a clear decrease in the average high-temperature, moving down from October's refreshing 61.3°F (16.3°C) to a chilly 46.9°F (8.3°C). Weather in November »
Weather in December
December, the first month of the winter in Port Byron, is also an icy month, with an average temperature fluctuating between 23.9°F (-4.5°C) and 34.5°F (1.4°C). The arrival of December indicates a decrease in the average high-temperature, moving from a frosty 46.9°F (8.3°C) in November to a cold 34.5°F (1.4°C). Weather in December »
Updated: Jul 19, 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
What is the coldest time of year?
January is the coldest month, with an average high-temperature of 28.2°F (-2.1°C) and an average low-temperature of 15.4°F (-9.2°C).
What is the most humid month?
January and July, with an average relative humidity of 83%, are most humid months.
How many days does it rain?
In Port Byron, during the entire year, the rain falls for 99.4 days and collects up to 9.57" (243mm) of precipitation.
When does it snow?
January through April, September through December are months with snowfall.
What is the snowiest month?
January is the month with the most snowfall. Snow falls for 7.2 days and accumulates 1.26" (32mm) of snow.
How much does it snow?
In Port Byron, during the entire year, snow falls for 24.5 days and aggregates up to 4.09" (104mm) of snow.
What is the month with the least sunshine?
The month with the least sunshine is January, with an average of 3.9h of sunshine.
When is the lowest UV index?
The month with the lowest UV index is January, with an average maximum UV index of 1.
When is Daylight Saving Time (DST)?
On Sunday, March 10. 2024, at 2:00 am, Daylight Saving Time starts, 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.
What is the wettest month?
The month with the most rainfall is May, when the rain falls for 13.4 days and typically aggregates up to 1.61" (41mm) of precipitation.
When it does not snow?
In Port Byron, snow does not fall in May through August.
When are the longest days?
June has the longest days of the year, with an average of 15h and 6min of daylight.
What month is the hottest?
July, noted for its average high-temperature of 81.7°F (27.6°C) and an average low-temperature of 64.8°F (18.2°C), is considered the warmest month.
What month has the most sunshine?
With an average of 10.1h of sunshine, July has the most sunshine of the year.
When is the highest UV index?
With an average maximum UV index of 6, July is the month with the highest UV index.
What is the least humid month?
With an average relative humidity of 71%, October is the least humid month.
What is the driest month?
The month with the least rainfall is December, when the rain falls for 4.1 days and typically collects 0.35" (9mm) of precipitation.
What is the month with the shortest days?
The month with the shortest days is December, with an average of 9h and 12min of daylight.
Average temperature
Port Byron, IL
The warmest month (with the highest average high temperature) is July (81.7°F).
The month with the lowest average high temperature is January (28.2°F).
The month with the highest average low temperature is July (64.8°F).
The coldest month (with the lowest average low temperature) is January (15.4°F).
Average pressure
Port Byron, IL
- Average pressure in January:
30.13"Hg - Average pressure in February:
30.12"Hg - Average pressure in March:
30.08"Hg - Average pressure in April:
29.93"Hg - Average pressure in May:
29.95"Hg - Average pressure in June:
29.91"Hg
- Average pressure in July:
29.96"Hg - Average pressure in August:
29.97"Hg - Average pressure in September:
30.02"Hg - Average pressure in October:
30.01"Hg - Average pressure in November:
30.09"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 (29.91"Hg).
Average wind speed
Port Byron, IL
- Average wind speed in January:
10.3mph - Average wind speed in February:
10.4mph - Average wind speed in March:
10.3mph - Average wind speed in April:
10.6mph - Average wind speed in May:
9mph - Average wind speed in June:
7.8mph
- Average wind speed in July:
6.8mph - Average wind speed in August:
6.7mph - Average wind speed in September:
7.8mph - Average wind speed in October:
9.5mph - Average wind speed in November:
10.3mph - Average wind speed in December:
9.8mph
The windiest month (with the highest average wind speed) is April (10.6mph).
The calmest month (with the lowest average wind speed) is August (6.7mph).
Average humidity
Port Byron, IL
The months with the highest relative humidity are January and July (83%).
The month with the lowest relative humidity is October (71%).
Average rainfall
Port Byron, IL
- Average rainfall in January:
0.43" - Average rainfall in February:
0.39" - Average rainfall in March:
0.63" - Average rainfall in April:
1.02" - Average rainfall in May:
1.61" - Average rainfall in June:
1.26"
- Average rainfall in July:
1.18" - Average rainfall in August:
0.71" - Average rainfall in September:
0.75" - Average rainfall in October:
0.71" - Average rainfall in November:
0.51" - Average rainfall in December:
0.35"
The wettest month (with the highest rainfall) is May (1.61").
The driest month (with the least rainfall) is December (0.35").
Average rainfall days
Port Byron, IL
- Average rainfall days in January:
3.2 days - Average rainfall days in February:
3.3 days - Average rainfall days in March:
8.2 days - Average rainfall days in April:
11.8 days - Average rainfall days in May:
13.4 days - Average rainfall days in June:
13.1 days
- Average rainfall days in July:
11.2 days - Average rainfall days in August:
10.7 days - Average rainfall days in September:
6.9 days - Average rainfall days in October:
8.4 days - Average rainfall days in November:
5.1 days - Average rainfall days in December:
4.1 days
The month with the highest number of rainy days is May (13.4 days).
The month with the least rainy days is January (3.2 days).
Average snowfall
Port Byron, IL
The month with the highest snowfall is January (1.26").
The months with the least snowfall are May, June, July and August (0").
Average snowfall days
Port Byron, IL
- Average snowfall days in January:
7.2 days - Average snowfall days in February:
6.2 days - Average snowfall days in March:
3.1 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:
0.1 days - Average snowfall days in October:
0.6 days - Average snowfall days in November:
1.5 days - Average snowfall days in December:
5 days
The month with the highest number of snowfall days is January (7.2 days).
The months with the least snowfall days are May, June, July and August (0 days).
Average daylight / Average sunshine
Port Byron, IL
- Average daylight in January:
9h and 4min - Average daylight in February:
10h and 4min - Average daylight in March:
12h and 0min - Average daylight in April:
13h and 2min - Average daylight in May:
14h and 3min - Average daylight in June:
15h and 1min
- Average daylight in July:
14h and 5min - Average daylight in August:
13h and 5min - Average daylight in September:
12h and 3min - Average daylight in October:
11h and 1min - Average daylight in November:
9h and 5min - Average daylight in December:
9h and 1min
The month with the longest days is June (Average daylight: 15h and 6min).
The month with the shortest days is December (Average daylight: 9h and 12min).
- Average sunshine in January:
3h and 5min - Average sunshine in February:
4h and 1min - Average sunshine in March:
6h and 2min - Average sunshine in April:
7h and 4min - Average sunshine in May:
8h and 4min - Average sunshine in June:
9h and 4min
- Average sunshine in July:
10h and 1min - Average sunshine in August:
9h and 5min - Average sunshine in September:
9h and 1min - Average sunshine in October:
5h and 3min - Average sunshine in November:
5h and 1min - Average sunshine in December:
4h and 1min
The month with the most sunshine is July (Average sunshine: 10h and 6min).
The month with the least sunshine is January (Average sunshine: 3h and 54min).
Average sunshine days
Port Byron, IL
- Average sunshine days in January:
22.2 days - Average sunshine days in February:
19.5 days - Average sunshine days in March:
19.8 days - Average sunshine days in April:
16.7 days - Average sunshine days in May:
14.6 days - Average sunshine days in June:
14.4 days
- Average sunshine days in July:
16.2 days - Average sunshine days in August:
17.4 days - Average sunshine days in September:
20.9 days - Average sunshine days in October:
21.3 days - Average sunshine days in November:
22.1 days - Average sunshine days in December:
22.4 days
The month with the most sunshine days is December (22.4 days).
The month with the least sunshine days is June (14.4 days).
Average UV index
Port Byron, IL
The month with the highest UV index is July (UV index 6).
The month with the lowest UV index is January (UV index 1).
Average cloud cover
Port Byron, IL
The month with the most cloud cover is January (Cloud cover 58).
The month with the least cloud cover is August (Cloud cover 30).
Average visibility
Port Byron, IL
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).
Port Byron, Illinois, USA
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