September weather forecastHarvard, IL
September
Weather in September
The first month of the autumn, September, is still a pleasant month in Harvard, Illinois, with an average temperature varying between 53.6°F (12°C) and 72.1°F (22.3°C).Temperature
A mild drop in Harvard's average high-temperature is observed in September, transitioning from a moderately hot 77.5°F (25.3°C) in August to a pleasant 72.1°F (22.3°C). September's average low-temperature reading settles at a cool 53.6°F (12°C).Humidity
In Harvard, the average relative humidity in September is 81%.Rainfall
In Harvard, in September, it is raining for 12.5 days, with typically 1.65" (42mm) of accumulated precipitation. In Harvard, during the entire year, the rain falls for 152.8 days and collects up to 26.46" (672mm) of precipitation.Snowfall
In Harvard, snow does not fall in June through September.Daylight
In Harvard, Illinois, the average length of the day in September is 12h and 28min.On the first day of the month, sunrise is at 6:20 am and sunset at 7:28 pm. On the last day of September, sunrise is at 6:51 am and sunset at 6:37 pm CDT.
Sunshine
The average sunshine in September is 8.4h.UV index
In September, the average daily maximum UV index is 4. A UV Index estimate of 3 to 5 represents a moderate health risk from unprotected exposure to Sun's UV rays for the average person.Note: The daily high UV index of 4 during September translates into the following recommendations:
Exercise prevention - Protecting skin and eyes from harm is required. The most potent solar radiation is around mid-day, so one should minimize exposure to direct sunlight during this period. Using UVA and UVB-protective sunglasses and sun-protective clothing is effective against UV radiation.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Harvard, IL
- Average high temperature in September: 72.1°F
The warmest month (with the highest average high temperature) is July (79.3°F).
The month with the lowest average high temperature is January (25.3°F).
- Average low temperature in September: 53.6°F
The month with the highest average low temperature is July (62.6°F).
The coldest month (with the lowest average low temperature) is January (13.3°F).
Average pressure in September
Harvard, IL
- Average pressure in September: 30.03"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 in September
Harvard, IL
- Average wind speed in September: 7.1mph
The windiest month (with the highest average wind speed) is April (9.9mph).
The calmest month (with the lowest average wind speed) is August (6.2mph).
Average humidity in September
Harvard, IL
- Average humidity in September: 81%
The month with the highest relative humidity is January (87%).
The months with the lowest relative humidity are April and October (77%).
Average rainfall in September
Harvard, IL
- Average rainfall in September: 1.65"
The wettest month (with the highest rainfall) is June (3.58").
The driest month (with the least rainfall) is December (1.3").
Average rainfall days in September
Harvard, IL
- Average rainfall days in September: 12.5 days
The month with the highest number of rainy days is May (18.8 days).
The month with the least rainy days is January (4.9 days).
Average snowfall in September
Harvard, IL
- Average snowfall in September: 0"
The month with the highest snowfall is January (4.41").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in September
Harvard, IL
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (14.3 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Harvard, IL
- Average daylight in September: 12h and 30min
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 6min).
- Average sunshine in September: 8h and 24min
The month with the most sunshine is July (Average sunshine: 9h and 36min).
The month with the least sunshine is January (Average sunshine: 3h and 30min).
Average sunshine days in September
Harvard, IL
- Average sunshine days in September: 15 days
The month with the most sunshine days is November (16.3 days).
The month with the least sunshine days is May (9.7 days).
Average UV index in September
Harvard, IL
- Average UV index in September: 4
The months with the highest UV index are May, June, July and August (UV index 5).
The months with the lowest UV index are January and December (UV index 1).
Average cloud cover in September
Harvard, IL
- Average cloud cover in September: 35
The month with the most cloud cover is January (Cloud cover 64).
The month with the least cloud cover is September (Cloud cover 35).
Average visibility in September
Harvard, IL
- Average visibility in September: 5mi
The months with the highest visibility are March, April, May, June, October and November (6mi).
The months with the lowest visibility are January, February, July, August, September and December (5mi).
