Contents
- Weather in May
- Frequently asked questions
- Average temperature in May
- Average pressure in May
- Average wind speed in May
- Average humidity in May
- Average rainfall in May
- Average rainfall days in May
- Average snowfall in May
- Average snowfall days in May
- Average daylight in May
- Average sunshine in May
- Average sunshine days in May
- Average UV index in May
- Average cloud cover in May
- Average visibility in May
Weather in May
Temperature
May's arrival sees a rise in the average high-temperature, jumping from April's comfortable 62.2°F (16.8°C) to an agreeable 72.9°F (22.7°C). Throughout May, an average low-temperature of 56.5°F (13.6°C) is expected.Humidity
In Illiopolis, the average relative humidity in May is 76%.Rainfall
The month with the most rainfall is May, when the rain falls for 17 days and typically aggregates up to 2.68" (68mm) of precipitation.Snowfall
May through October are months without snowfall in Illiopolis.Daylight
The average length of the day in May is 14h and 24min.On the first day of the month, sunrise is at 5:56 am and sunset at 7:51 pm. On the last day of May, sunrise is at 5:30 am and sunset at 8:18 pm CDT.
Sunshine
In May, the average sunshine in Illiopolis is 9.1h.UV index
In May, the average daily maximum UV index is 5. 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: In May, a daily UV index of 5 turns into the following recommendations:
Exercise prevention - Protecting skin and eyes from harm is required. When the Sun is at its strongest around midday, find shade and limit exposure. A wide-brimmed hat is a shield, deflecting up to 50% of harmful UV radiation from eyes.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What is the average May temperature?
What is the average humidity in May?
What is the rainiest month?
How much does it rain in May?
When it does not snow in Illiopolis?
Does it snow in May?
What is the average length of the day in May?
When is the sunrise / sunset in May in Illiopolis?
How long on average sun shines in May?
What is the UV index intensity in May?
Average temperature in May
Illiopolis, IL
- Average high temperature in May: 72.9°F
The warmest month (with the highest average high temperature) is July (82°F).
The month with the lowest average high temperature is January (32.5°F).
- Average low temperature in May: 56.5°F
The month with the highest average low temperature is July (65.7°F).
The coldest month (with the lowest average low temperature) is January (20.5°F).
Average pressure in May
Illiopolis, IL
- Average pressure in May: 29.95"Hg
The month with the highest atmospheric pressure is January (30.15"Hg).
The month with the lowest atmospheric pressure is June (29.92"Hg).
Average wind speed in May
Illiopolis, IL
- Average wind speed in May: 8.8mph
The windiest month (with the highest average wind speed) is April (10.6mph).
The calmest months (with the lowest average wind speed) are July and August (6.3mph).
Average humidity in May
Illiopolis, IL
- Average humidity in May: 76%
The month with the highest relative humidity is July (84%).
The month with the lowest relative humidity is October (70%).
Average rainfall in May
Illiopolis, IL
- Average rainfall in May: 2.68"
The wettest month (with the highest rainfall) is May (2.68").
The driest month (with the least rainfall) is December (1.1").
Average rainfall days in May
Illiopolis, IL
- Average rainfall days in May: 17 days
The month with the highest number of rainy days is May (17 days).
The months with the least rainy days are January and February (6.3 days).
Average snowfall in May
Illiopolis, IL
- Average snowfall in May: 0"
The month with the highest snowfall is January (2.24").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in May
Illiopolis, IL
- Average snowfall days in May: 0 days
The month with the highest number of snowfall days is January (9.4 days).
The months with the least snowfall days are May, June, July and August (0 days).
Average daylight in May /
Average sunshine in May
Illiopolis, IL
- Average daylight in May: 14h 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 May: 9h and 1min
The month with the most sunshine is June (Average sunshine: 10h and 12min).
The month with the least sunshine is January (Average sunshine: 4h and 0min).
Average sunshine days in May
Illiopolis, IL
- Average sunshine days in May: 10.8 days
The month with the most sunshine days is November (18.9 days).
The month with the least sunshine days is May (10.8 days).
Average UV index in May
Illiopolis, IL
- Average UV index in May: 5
The months with the highest UV index are June, July and August (UV index 6).
The month with the lowest UV index is January (UV index 1).
Average cloud cover in May
Illiopolis, IL
- Average cloud cover in May: 40
The month with the most cloud cover is January (Cloud cover 57).
The months with the least cloud cover are June and September (Cloud cover 31).
Average visibility in May
Illiopolis, IL
- Average visibility in May: 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).
Illiopolis, Illinois, USA
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