Contents
- Weather in September
- Frequently asked questions
- Average temperature in September
- Average pressure in September
- Average wind speed in September
- Average humidity in September
- Average rainfall in September
- Average rainfall days in September
- Average snowfall in September
- Average snowfall days in September
- Average daylight in September
- Average sunshine in September
- Average sunshine days in September
- Average UV index in September
- Average cloud cover in September
- Average visibility in September
Weather in September
Temperature
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). San Jose, during the month of September, experiences an average low-temperature of 57.9°F (14.4°C).Humidity
In September, the average relative humidity is 76%.Rainfall
In San Jose, in September, during 10.3 rainfall days, 1.57" (40mm) of precipitation is typically accumulated. In San Jose, during the entire year, the rain falls for 131.4 days and collects up to 20.08" (510mm) of precipitation.Snowfall
May through October are months without snowfall.Daylight
In September, the average length of the day is 12h and 26min.On the first day of the month, sunrise is at 6:26 am and sunset at 7:29 pm. On the last day of September, sunrise is at 6:54 am and sunset at 6:41 pm CDT.
Sunshine
In September, the average sunshine in San Jose is 9.1h.UV index
The average daily maximum UV index in September is 5. A UV Index value of 3 to 5 symbolizes a moderate threat to health from exposure to the Sun's UV rays for ordinary individuals.Note: The daily high UV index of 5 in September translates into this advice:
Take measures. Individuals with light skin might experience burns in under 30 minutes. UV radiation from the Sun is most dangerous during midday; take precautions and seek shade. Shield yourself from the harmful effects of UV radiation with sun-protective attire, a hat, and quality sunglasses.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What are the temperatures in September?
What is the average humidity in September?
How much does it rain in September?
When it does not snow?
What is the average length of the day in September?
When is the sunrise / sunset in September?
How long on average sun shines in September?
What is the UV index reading in September?
Average temperature in September
San Jose, IL
- Average high temperature in September: 76.5°F
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).
- Average low temperature in September: 57.9°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 in September
San Jose, IL
- Average pressure in September: 30.03"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 in September
San Jose, IL
- Average wind speed in September: 7.5mph
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 in September
San Jose, IL
- Average humidity in September: 76%
The month with the highest relative humidity is July (84%).
The month with the lowest relative humidity is October (71%).
Average rainfall in September
San Jose, IL
- Average rainfall in September: 1.57"
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 in September
San Jose, IL
- Average rainfall days in September: 10.3 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 in September
San Jose, IL
- Average snowfall in September: 0"
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 in September
San Jose, IL
- Average snowfall days in September: 0 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 in September /
Average sunshine in September
San Jose, IL
- Average daylight in September: 12h and 2min
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 September: 9h and 1min
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 in September
San Jose, IL
- Average sunshine days in September: 18.8 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 in September
San Jose, IL
- Average UV index in September: 5
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 in September
San Jose, IL
- Average cloud cover in September: 30
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 in September
San Jose, IL
- Average visibility in September: 6mi
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).
San Jose, Illinois, USA
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