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
In Williamsville, stepping into April brings a temperature increase, moving up from March's cool 51.1°F (10.6°C) to a comfortable 63.1°F (17.3°C). During April, Williamsville's temperature falls to a steady low-temperature average of 46.2°F (7.9°C).Humidity
The average relative humidity in April is 74%.Rainfall
In Williamsville, in April, during 13.6 rainfall days, 2.05" (52mm) of precipitation is typically accumulated. Throughout the year, there are 131.5 rainfall days, and 18.54" (471mm) of precipitation is accumulated.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. Throughout the year, there are 24.5 snowfall days, and 5.51" (140mm) of snow is accumulated.Daylight
In April, the average length of the day is 13h and 17min.On the first day of the month, sunrise is at 6:40 am and sunset at 7:22 pm. On the last day of April, in Williamsville, Illinois, sunrise is at 5:58 am and sunset at 7:52 pm CDT.
Sunshine
In April, the average sunshine in Williamsville is 8.2h.UV index
In April, the average daily maximum UV index is 4. A UV Index reading of 3 to 5 represents a medium health hazard from exposure to the Sun's UV rays for ordinary individuals.Note: The UV index of 4 in April translates into these instructions:
Ensure safety - Imperative it is to shield skin and eyes from damage. Being exposed to the midday Sun can have harmful effects due to strong UV radiation; always take precautions. Sun-related eye harm can be minimized with proper sunglasses offering UVA and UVB coverage. Be advised! The UV radiation from the Sun can be almost doubled due to the reflective properties of snow.
Frequently asked questions
What is the temperature in April in Williamsville?
What is the average humidity in April in Williamsville?
How many days does it rain in April in Williamsville?
What is the last month it snows in Williamsville?
What is the average length of the day in April in Williamsville?
When are sunrise and sunset in April in Williamsville?
How many hours of sunshine does Williamsville have in April?
How high is the UV index in April in Williamsville?
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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