April weather forecastSullivan, IL
April
Weather in April
April in Sullivan, Illinois, is an enjoyable spring month, with temperature in the range of an average low of 46°F (7.8°C) and an average high of 62.2°F (16.8°C).Temperature
With the onset of April, the average high-temperature slightly shifts from March's fresh 50.5°F (10.3°C) to a comfortable 62.2°F (16.8°C). Throughout April, an average low-temperature of 46°F (7.8°C) is expected in Sullivan, Illinois.Humidity
In Sullivan, the average relative humidity in April is 75%.Rainfall
In Sullivan, in April, it is raining for 13.8 days, with typically 1.65" (42mm) of accumulated precipitation. In Sullivan, during the entire year, the rain falls for 130.9 days and collects up to 15.43" (392mm) of precipitation.Snowfall
Months with snowfall in Sullivan are January through April, November and December. April is the last month it regularly snows. During 0.5 snowfall days, in April, Sullivan aggregates 0.04" (1mm) of snow. In Sullivan, during the entire year, snow falls for 21.5 days and aggregates up to 4.53" (115mm) of snow.Daylight
The average length of the day in April is 13h and 17min.On the first day of the month, sunrise is at 6:37 am and sunset at 7:18 pm. On the last day of April, sunrise is at 5:55 am and sunset at 7:47 pm CDT.
Sunshine
In April, the average sunshine in Sullivan is 8.2h.UV index
In April, the average daily maximum UV index is 4. A UV Index estimate of 3 to 5 represents a moderate threat to health from unprotected exposure to Sun's UV rays for average individuals.Note: A daily high UV index of 4 in April leads to these guidelines:
Put precautions into practice - Guidance to elude sunburn is provided. Minimize direct exposure to the Sun during midday when its radiation is at its peak. Fend off the sun's harsh rays with appropriate clothing, a wide-brim hat, and UV-protective sunglasses. Attention! Nearly twice the Sun's UV radiation can be reflected by snow.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in April
Sullivan, IL
- Average high temperature in April: 62.2°F
The warmest month (with the highest average high temperature) is July (82.2°F).
The month with the lowest average high temperature is January (33.6°F).
- Average low temperature in April: 46°F
The month with the highest average low temperature is July (65.8°F).
The coldest month (with the lowest average low temperature) is January (21.6°F).
Average pressure in April
Sullivan, 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 (29.93"Hg).
Average wind speed in April
Sullivan, IL
- Average wind speed in April: 10.4mph
The windiest month (with the highest average wind speed) is January (10.7mph).
The calmest months (with the lowest average wind speed) are July and August (6.3mph).
Average humidity in April
Sullivan, IL
- Average humidity in April: 75%
The month with the highest relative humidity is July (84%).
The month with the lowest relative humidity is October (70%).
Average rainfall in April
Sullivan, IL
- Average rainfall in April: 1.65"
The wettest month (with the highest rainfall) is June (1.85").
The driest month (with the least rainfall) is February (0.71").
Average rainfall days in April
Sullivan, IL
- Average rainfall days in April: 13.8 days
The month with the highest number of rainy days is May (16.3 days).
The month with the least rainy days is February (5.9 days).
Average snowfall in April
Sullivan, IL
- Average snowfall in April: 0.04"
The month with the highest snowfall is January (1.54").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in April
Sullivan, IL
- Average snowfall days in April: 0.5 days
The month with the highest number of snowfall days is January (6.4 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
Sullivan, IL
- Average daylight in April: 13h and 18min
The month with the longest days is June (Average daylight: 14h and 54min).
The month with the shortest days is December (Average daylight: 9h and 24min).
- Average sunshine in April: 8h and 12min
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
Sullivan, IL
- Average sunshine days in April: 14.9 days
The month with the most sunshine days is October (20.5 days).
The month with the least sunshine days is May (12.3 days).
Average UV index in April
Sullivan, 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
Sullivan, IL
- Average cloud cover in April: 44
The month with the most cloud cover is January (Cloud cover 56).
The month with the least cloud cover is June (Cloud cover 30).
Average visibility in April
Sullivan, 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).





