Contents
- Weather in April
- Frequently asked questions
- Average temperature in April
- Average pressure in April
- Average wind speed in April
- Average humidity in April
- Average rainfall in April
- Average rainfall days in April
- Average snowfall in April
- Average snowfall days in April
- Average daylight in April
- Average sunshine in April
- Average sunshine days in April
- Average UV index in April
- Average cloud cover in April
- Average visibility in April
Weather in April
Temperature
The arrival of April signals an increase in the average high-temperature, moving from a cool 51.1°F (10.6°C) in March to a comfortable 63.1°F (17.3°C). During April, the temperature tends to dip to an average of 46.2°F (7.9°C) at night.Humidity
In April, the average relative humidity is 74%.Rainfall
In Williamsville, in April, during 13.6 rainfall days, 2.05" (52mm) of precipitation is typically accumulated. In Williamsville, during the entire year, the rain falls for 131.5 days and collects up to 18.54" (471mm) of precipitation.Snowfall
Months with snowfall are January through April, November and December. April is the last month it regularly snows. During 0.5 snowfall days, in April, Williamsville aggregates 0.04" (1mm) of snow. In Williamsville, during the entire year, snow falls for 24.5 days and aggregates up to 5.51" (140mm) of snow.Daylight
In Williamsville, the average length of the day in April is 13h and 17min.On the first day of April, sunrise is at 6:40 am and sunset at 7:22 pm. On the last day of the month, sunrise is at 5:58 am and sunset at 7:52 pm CDT.
Sunshine
In Williamsville, the average sunshine in April is 8.2h.UV index
In April, the average daily maximum UV index is 4. A UV Index of 3 to 5 symbolizes a medium vulnerability from unsafe exposure to UV radiation for the average person.Note: In April, a daily UV index of 4 turns into the following recommendations:
Take necessary precautions - Protection from skin and eye injury is mandatory. Midday Sun has the strongest UV rays, making it crucial to limit exposure and find shade. Stay sun-safe with clothing that is both closely woven and worn loosely. Be aware! The reflective nature of snow can magnify the Sun's UV radiation almost twofold.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What are the temperatures in April?
What is the average humidity in April?
How much does it rain in April?
What is the last month it snows?
How many hours of daylight does Williamsville have in April?
When are sunrise and sunset in April in Williamsville?
How many hours of sunshine does Williamsville have in April?
What is the UV index intensity in April?
Average temperature in April
Williamsville, IL
- Average high temperature in April: 63.1°F
The warmest month (with the highest average high temperature) is July (82.8°F).
The month with the lowest average high temperature is January (33.1°F).
- Average low temperature in April: 46.2°F
The month with the highest average low temperature is July (66°F).
The coldest month (with the lowest average low temperature) is January (20.8°F).
Average pressure in April
Williamsville, IL
- Average pressure in April: 29.94"Hg
The month with the highest atmospheric pressure is January (30.15"Hg).
The month with the lowest atmospheric pressure is June (29.91"Hg).
Average wind speed in April
Williamsville, IL
- Average wind speed in April: 10.4mph
The windiest months (with the highest average wind speed) are January and April (10.4mph).
The calmest months (with the lowest average wind speed) are July and August (6.2mph).
Average humidity in April
Williamsville, IL
- Average humidity in April: 74%
The month with the highest relative humidity is July (84%).
The month with the lowest relative humidity is October (70%).
Average rainfall in April
Williamsville, IL
- Average rainfall in April: 2.05"
The wettest month (with the highest rainfall) is June (2.36").
The driest month (with the least rainfall) is December (0.83").
Average rainfall days in April
Williamsville, IL
- Average rainfall days in April: 13.6 days
The month with the highest number of rainy days is May (17 days).
The month with the least rainy days is February (5.7 days).
Average snowfall in April
Williamsville, IL
- Average snowfall in April: 0.04"
The month with the highest snowfall is January (1.81").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in April
Williamsville, IL
- Average snowfall days in April: 0.5 days
The month with the highest number of snowfall days is January (8 days).
The months with the least snowfall days are May, June, July, August and September (0 days).
Average daylight in April /
Average sunshine in April
Williamsville, IL
- Average daylight in April: 13h 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 April: 8h and 1min
The month with the most sunshine is June (Average sunshine: 10h and 24min).
The month with the least sunshine is January (Average sunshine: 4h and 6min).
Average sunshine days in April
Williamsville, IL
- Average sunshine days in April: 13.8 days
The month with the most sunshine days is December (20.5 days).
The month with the least sunshine days is May (11.5 days).
Average UV index in April
Williamsville, IL
- Average UV index in April: 4
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 April
Williamsville, IL
- Average cloud cover in April: 44
The month with the most cloud cover is January (Cloud cover 55).
The months with the least cloud cover are June, August and September (Cloud cover 30).
Average visibility in April
Williamsville, IL
- Average visibility in April: 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).
Williamsville, Illinois, USA
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