Climate and monthly weather forecastSan Jose, IL
Climate and monthly weather forecast
Weather in January
January, the same as December, in San Jose, Illinois, is another subzero cold winter month, with an average temperature varying between 31.5°F (-0.3°C) and 19.8°F (-6.8°C). January is San Jose's coldest month, registering average high temperatures of 31.5°F (-0.3°C) and lows of 19.8°F (-6.8°C). Weather in January »Weather in February
The last month of the winter, February, is an icy month in San Jose, Illinois, with an average temperature ranging between min 23.4°F (-4.8°C) and max 36.3°F (2.4°C). San Jose, Illinois, marks the arrival of February with an average high-temperature of an icy 36.3°F (2.4°C), hardly different from January's 31.5°F (-0.3°C). Weather in February »Weather in March
March, the first month of the spring in San Jose, is a frosty month, with an average temperature ranging between min 34.5°F (1.4°C) and max 49.6°F (9.8°C). An escalation in the average high-temperature is seen with the onset of March, moving from an icy 36.3°F (2.4°C) in February to a frosty 49.6°F (9.8°C). Weather in March »Weather in April
April is a comfortable spring month in San Jose, Illinois, with an average temperature ranging between max 61.5°F (16.4°C) and min 44.6°F (7°C). April brings a rise in the average high-temperature, transitioning from March's frosty 49.6°F (9.8°C) to an enjoyable 61.5°F (16.4°C). Weather in April »Weather in May
May, the last month of the spring in San Jose, is an agreeable month, with an average temperature ranging between min 55.8°F (13.2°C) and max 72.1°F (22.3°C). May shows a rise in the average high-temperature, moving from April's refreshing 61.5°F (16.4°C) to an agreeable 72.1°F (22.3°C). Weather in May »Weather in June
June, the first month of the summer in San Jose, is a warm month, with an average temperature ranging between min 63.9°F (17.7°C) and max 80.6°F (27°C). San Jose in June observes a minor temperature shift, with average high-temperatures adjusting from an agreeable 72.1°F (22.3°C) in May to a moderately hot 80.6°F (27°C). Weather in June »Weather in July
July, like June, in San Jose, Illinois, is a moderately hot summer month, with an average temperature fluctuating between 82°F (27.8°C) and 65.3°F (18.5°C). The warmest period tends to be July, when average temperatures fluctuate between a high of 82°F (27.8°C) and a low of 65.3°F (18.5°C). The heat index for July is estimated at a hot 89.6°F (32°C). Weather in July »Weather in August
August, the last month of the summer in San Jose, is also a moderately hot month, with an average temperature fluctuating between 81.1°F (27.3°C) and 63.5°F (17.5°C). San Jose in August witnesses an average high-temperature of a still warm 81.1°F (27.3°C), indicating a slight variation from July's 82°F (27.8°C). Weather in August »Weather in September
September, the first month of the autumn in San Jose, is still a warm month, with temperature in the range of an average high of 76.5°F (24.7°C) and an average low of 57.9°F (14.4°C). San Jose experiences an average high-temperature of a still warm 76.5°F (24.7°C) with the onset of September, subtly varied from August's 81.1°F (27.3°C). Weather in September »Weather in October
October, the same as September, is another comfortable autumn month in San Jose, Illinois, with temperature in the range of an average low of 46.9°F (8.3°C) and an average high of 63.1°F (17.3°C). In October, the average high-temperature decreases from a warm 76.5°F (24.7°C) in September to a comfortable 63.1°F (17.3°C). Weather in October »Weather in November
November, the last month of the autumn in San Jose, is also a frosty month, with an average temperature fluctuating between 35.2°F (1.8°C) and 48.9°F (9.4°C). November brings a minor decrease, with the average high-temperature reducing from a refreshing 63.1°F (17.3°C) in October to a chilly 48.9°F (9.4°C). Weather in November »Weather in December
December, the first month of the winter in San Jose, is also a wintry month, with an average temperature ranging between max 36.9°F (2.7°C) and min 26.4°F (-3.1°C). Transition into December marks a drop in the average high-temperature, moving from a frosty 48.9°F (9.4°C) in November to a wintry 36.9°F (2.7°C). Weather in December »Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature
San Jose, IL
The warmest month (with the highest average high temperature) is July (82°F).
The month with the lowest average high temperature is January (31.5°F).
The month with the highest average low temperature is July (65.3°F).
The coldest month (with the lowest average low temperature) is January (19.8°F).
Average pressure
San Jose, IL
- Average pressure in January:
30.14"Hg - Average pressure in February:
30.12"Hg - Average pressure in March:
30.08"Hg - Average pressure in April:
29.94"Hg - Average pressure in May:
29.95"Hg - Average pressure in June:
29.91"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:
30.12"Hg
The month with the highest atmospheric pressure is January (30.14"Hg).
The month with the lowest atmospheric pressure is June (29.91"Hg).
Average wind speed
San Jose, IL
- Average wind speed in January:
10.4mph - 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:
8.8mph - Average wind speed in June:
7.7mph
- Average wind speed in July:
6.5mph - Average wind speed in August:
6.4mph - Average wind speed in September:
7.5mph - Average wind speed in October:
9.3mph - Average wind speed in November:
9.9mph - 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 (6.4mph).
Average humidity
San Jose, IL
The month with the highest relative humidity is July (84%).
The month with the lowest relative humidity is October (71%).
Average rainfall
San Jose, IL
- Average rainfall in January:
1.06" - Average rainfall in February:
1.02" - Average rainfall in March:
1.57" - Average rainfall in April:
2.28" - Average rainfall in May:
2.83" - Average rainfall in June:
2.28"
- Average rainfall in July:
1.89" - Average rainfall in August:
1.61" - Average rainfall in September:
1.57" - Average rainfall in October:
1.61" - Average rainfall in November:
1.26" - Average rainfall in December:
1.06"
The wettest month (with the highest rainfall) is May (2.83").
The driest month (with the least rainfall) is February (1.02").
Average rainfall days
San Jose, IL
- Average rainfall days in January:
5.3 days - Average rainfall days in February:
5.1 days - Average rainfall days in March:
11.8 days - Average rainfall days in April:
13.3 days - Average rainfall days in May:
17.7 days - Average rainfall days in June:
15.7 days
- Average rainfall days in July:
15.5 days - Average rainfall days in August:
12.4 days - Average rainfall days in September:
10.3 days - Average rainfall days in October:
9.8 days - Average rainfall days in November:
7.9 days - Average rainfall days in December:
6.6 days
The month with the highest number of rainy days is May (17.7 days).
The month with the least rainy days is February (5.1 days).
Average snowfall
San Jose, IL
The month with the highest snowfall is January (2.87").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days
San Jose, IL
- Average snowfall days in January:
8.4 days - Average snowfall days in February:
6.4 days - Average snowfall days in March:
3.2 days - Average snowfall days in April:
0.5 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:
1.7 days - Average snowfall days in December:
5.4 days
The month with the highest number of snowfall days is January (8.4 days).
The months with the least snowfall days are May, June, July, August and September (0 days).
Average daylight / Average sunshine
San Jose, IL
- Average daylight in January:
9h and 42min - 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 24min - Average daylight in June:
15h and 0min
- Average daylight in July:
14h and 42min - Average daylight in August:
13h and 42min - Average daylight in September:
12h and 24min - Average daylight in October:
11h and 6min - Average daylight in November:
10h and 0min - Average daylight in December:
9h and 24min
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 24min).
- Average sunshine in January:
4h and 0min - Average sunshine in February:
4h and 18min - Average sunshine in March:
6h and 30min - Average sunshine in April:
8h and 6min - Average sunshine in May:
9h and 6min - Average sunshine in June:
10h and 12min
- Average sunshine in July:
9h and 54min - Average sunshine in August:
9h and 48min - Average sunshine in September:
9h and 6min - Average sunshine in October:
5h and 48min - Average sunshine in November:
5h and 18min - Average sunshine in December:
4h and 24min
The month with the most sunshine is June (Average sunshine: 10h and 12min).
The month with the least sunshine is January (Average sunshine: 4h and 0min).
Average sunshine days
San Jose, IL
- Average sunshine days in January:
18.3 days - Average sunshine days in February:
17.6 days - Average sunshine days in March:
16.1 days - Average sunshine days in April:
14.8 days - Average sunshine days in May:
11.8 days - Average sunshine days in June:
12 days
- Average sunshine days in July:
12 days - Average sunshine days in August:
15.3 days - Average sunshine days in September:
18.8 days - Average sunshine days in October:
19.4 days - Average sunshine days in November:
20 days - Average sunshine days in December:
19.7 days
The month with the most sunshine days is November (20 days).
The month with the least sunshine days is May (11.8 days).
Average UV index
San Jose, IL
The months with the highest UV index are June, July and August (UV index 6).
The months with the lowest UV index are January, February, November and December (UV index 2).
Average cloud cover
San Jose, IL
The month with the most cloud cover is January (Cloud cover 57).
The month with the least cloud cover is September (Cloud cover 30).
Average visibility
San Jose, 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).





