April weather forecastO'Fallon, IL
April
Weather in April
April is an enjoyable spring month in O'Fallon, Illinois, with an average temperature fluctuating between 47.8°F (8.8°C) and 64.9°F (18.3°C).Temperature
April's arrival sees a rise in the average high-temperature, jumping from March's fresh 54.5°F (12.5°C) to an enjoyable 64.9°F (18.3°C). During April, O'Fallon experiences an average low-temperature of 47.8°F (8.8°C) at night.Humidity
In O'Fallon, Illinois, the average relative humidity in April is 77%.Rainfall
In O'Fallon, in April, during 12.3 rainfall days, 1.1" (28mm) of precipitation is typically accumulated. In O'Fallon, during the entire year, the rain falls for 108.8 days and collects up to 10.24" (260mm) of precipitation.Snowfall
April through October are months without snowfall.Daylight
In O'Fallon, the average length of the day in April is 13h and 14min.On the first day of April, sunrise is at 6:43 am and sunset at 7:23 pm. On the last day of the month, sunrise is at 6:02 am and sunset at 7:51 pm CDT.
Sunshine
In O'Fallon, the average sunshine in April is 8.6h.UV index
In O'Fallon, the average daily maximum UV index in April is 4. A UV Index value of 3 to 5 symbolizes a moderate threat to health from unsafe exposure to UV radiation for the average person.Note: A maximum high daily UV index of 4 during April translates into the following directions:
Be vigilant - Suggestions to stave off sun damage are provided. UV radiation from the Sun is most dangerous during midday; take precautions and seek shade. A wide-brimmed hat is a staple for defending the face, eyes, ears, and neck from the Sun. Be watchful! The reflection of snow can enhance the intensity of the Sun's UV radiation nearly double.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in April
O'Fallon, IL
- Average high temperature in April: 64.9°F
The warmest month (with the highest average high temperature) is July (85.6°F).
The month with the lowest average high temperature is January (37.8°F).
- Average low temperature in April: 47.8°F
The month with the highest average low temperature is July (68.2°F).
The coldest month (with the lowest average low temperature) is January (24.6°F).
Average pressure in April
O'Fallon, IL
- Average pressure in April: 29.94"Hg
The month with the highest atmospheric pressure is January (30.16"Hg).
The month with the lowest atmospheric pressure is June (29.93"Hg).
Average wind speed in April
O'Fallon, IL
- Average wind speed in April: 9.1mph
The windiest month (with the highest average wind speed) is January (9.5mph).
The calmest month (with the lowest average wind speed) is July (5.6mph).
Average humidity in April
O'Fallon, IL
- Average humidity in April: 77%
The months with the highest relative humidity are May, July and August (79%).
The month with the lowest relative humidity is October (70%).
Average rainfall in April
O'Fallon, IL
- Average rainfall in April: 1.1"
The wettest month (with the highest rainfall) is July (1.42").
The driest month (with the least rainfall) is December (0.31").
Average rainfall days in April
O'Fallon, IL
- Average rainfall days in April: 12.3 days
The month with the highest number of rainy days is July (13.1 days).
The month with the least rainy days is December (4.6 days).
Average snowfall in April
O'Fallon, IL
- Average snowfall in April: 0"
The month with the highest snowfall is January (0.51").
The months with the least snowfall are April, May, June, July, August, September and October (0").
Average snowfall days in April
O'Fallon, IL
- Average snowfall days in April: 0.1 days
The month with the highest number of snowfall days is January (4.7 days).
The months with the least snowfall days are May, June, July, August, September and October (0 days).
Average daylight in April /
Average sunshine in April
O'Fallon, IL
- Average daylight in April: 13h and 12min
The month with the longest days is June (Average daylight: 14h and 48min).
The month with the shortest days is December (Average daylight: 9h and 30min).
- Average sunshine in April: 8h and 36min
The months with the most sunshine are June and July (Average sunshine: 10h and 24min).
The month with the least sunshine is January (Average sunshine: 4h and 30min).
Average sunshine days in April
O'Fallon, IL
- Average sunshine days in April: 15.8 days
The month with the most sunshine days is December (23.6 days).
The months with the least sunshine days are May and July (15.5 days).
Average UV index in April
O'Fallon, IL
- Average UV index in April: 4
The months with the highest UV index are May, 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 April
O'Fallon, IL
- Average cloud cover in April: 42
The month with the most cloud cover is January (Cloud cover 51).
The month with the least cloud cover is August (Cloud cover 28).
Average visibility in April
O'Fallon, IL
- Average visibility in April: 6mi
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).
