May weather forecastCastleton, IL
May
Weather in May
The last month of the spring, May, is an agreeable month in Castleton, Illinois, with an average temperature varying between 71.1°F (21.7°C) and 54.1°F (12.3°C).Temperature
The onset of May brings a temperature shift, with the average high-temperature moving from a refreshing 59.7°F (15.4°C) in April to an agreeable 71.1°F (21.7°C). Throughout May, Castleton experiences a low-temperature average of 54.1°F (12.3°C).Humidity
In Castleton, the average relative humidity in May is 78%.Rainfall
May is the month with the most rainfall in Castleton. Rain falls for 15.2 days and accumulates 2.24" (57mm) of precipitation.Snowfall
May through September are months without snowfall in Castleton, Illinois.Daylight
In May, the average length of the day is 14h and 30min.On the first day of the month, sunrise is at 5:55 am and sunset at 7:56 pm. On the last day of May, in Castleton, sunrise is at 5:28 am and sunset at 8:24 pm CDT.
Sunshine
In May, the average sunshine is 8.8h.UV index
In Castleton, the average daily maximum UV index in May is 5. A UV Index value of 3 to 5 symbolizes a moderate health risk from unsafe exposure to UV radiation for ordinary individuals.Note: In May, a regular UV index of 5 translates into these guidelines:
Exercise caution. The susceptibility of light skin individuals to burns is less than 30 minutes. Being in direct Sun during midday can be harmful due to intense solar radiation; take precautions. In the presence of strong sunlight, it's crucial to wear sunglasses that ward off UVA and UVB rays.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in May
Castleton, IL
- Average high temperature in May: 71.1°F
The warmest month (with the highest average high temperature) is July (81.1°F).
The month with the lowest average high temperature is January (29.7°F).
- Average low temperature in May: 54.1°F
The month with the highest average low temperature is July (64.8°F).
The coldest month (with the lowest average low temperature) is January (17.8°F).
Average pressure in May
Castleton, IL
- Average pressure in May: 29.95"Hg
The month with the highest atmospheric pressure is January (30.14"Hg).
The month with the lowest atmospheric pressure is June (29.91"Hg).
Average wind speed in May
Castleton, IL
- Average wind speed in May: 9mph
The windiest month (with the highest average wind speed) is April (10.7mph).
The calmest month (with the lowest average wind speed) is August (6.6mph).
Average humidity in May
Castleton, IL
- Average humidity in May: 78%
The month with the highest relative humidity is July (84%).
The month with the lowest relative humidity is October (72%).
Average rainfall in May
Castleton, IL
- Average rainfall in May: 2.24"
The wettest month (with the highest rainfall) is May (2.24").
The driest month (with the least rainfall) is January (0.59").
Average rainfall days in May
Castleton, IL
- Average rainfall days in May: 15.2 days
The month with the highest number of rainy days is May (15.2 days).
The months with the least rainy days are January and February (4.2 days).
Average snowfall in May
Castleton, IL
- Average snowfall in May: 0"
The month with the highest snowfall is January (1.81").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in May
Castleton, IL
- Average snowfall days in May: 0 days
The month with the highest number of snowfall days is January (8.6 days).
The months with the least snowfall days are May, June, July, August and September (0 days).
Average daylight in May /
Average sunshine in May
Castleton, IL
- Average daylight in May: 14h and 30min
The month with the longest days is June (Average daylight: 15h and 6min).
The month with the shortest days is December (Average daylight: 9h and 18min).
- Average sunshine in May: 8h and 48min
The months with the most sunshine are June and July (Average sunshine: 10h and 0min).
The month with the least sunshine is January (Average sunshine: 3h and 54min).
Average sunshine days in May
Castleton, IL
- Average sunshine days in May: 12.8 days
The month with the most sunshine days is November (21.3 days).
The month with the least sunshine days is May (12.8 days).
Average UV index in May
Castleton, IL
- Average UV index in May: 5
The months with the highest UV index are June and July (UV index 6).
The months with the lowest UV index are January and December (UV index 1).
Average cloud cover in May
Castleton, IL
- Average cloud cover in May: 41
The month with the most cloud cover is January (Cloud cover 58).
The month with the least cloud cover is September (Cloud cover 30).
Average visibility in May
Castleton, 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).
