May weather forecastAlto Pass, IL
May
Weather in May
The last month of the spring, May, is a warm month in Alto Pass, Illinois, with temperature in the range of an average low of 58.1°F (14.5°C) and an average high of 75.7°F (24.3°C).Temperature
The onset of May brings a rise in the average high-temperature, elevating from a comfortable 66.6°F (19.2°C) in April to a warm 75.7°F (24.3°C). Alto Pass experiences an average low-temperature reading of 58.1°F (14.5°C) throughout May.Humidity
May is the most humid month, with an average relative humidity of 79%.Rainfall
In May, in Alto Pass, the rain falls for 14.9 days. Throughout May, 2.95" (75mm) of precipitation is accumulated. Throughout the year, in Alto Pass, there are 143 rainfall days, and 27.44" (697mm) of precipitation is accumulated.Snowfall
May through September are months without snowfall.Daylight
The average length of the day in May is 14h and 13min.On the first day of the month, sunrise is at 6:00 am and sunset at 7:47 pm. On the last day of May, sunrise is at 5:37 am and sunset at 8:12 pm CDT.
Sunshine
The average sunshine in May is 9.1h.UV index
May through August, with an average maximum UV index of 6, are months with the highest UV index. A UV Index estimate of 6 to 7 represents a high health vulnerability from unsafe exposure to UV radiation for average individuals.Note: A daily high UV index of 6 in May leads to these guidelines:
Guard against overexposure. Protection from sun-induced harm is essential. Avoid exposure to the Sun and try to stay in the shade between 10 a.m. and 4 p.m., when UV radiation is most potent, but be aware that parasols or canopies may not offer full protection. In bright sunlight, prioritize sunglasses that grant protection from UVA and UVB radiation.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in May
Alto Pass, IL
- Average high temperature in May: 75.7°F
The warmest month (with the highest average high temperature) is July (88.3°F).
The month with the lowest average high temperature is January (39.7°F).
- Average low temperature in May: 58.1°F
The month with the highest average low temperature is July (69.1°F).
The coldest month (with the lowest average low temperature) is January (26.8°F).
Average pressure in May
Alto Pass, IL
- Average pressure in May: 29.97"Hg
The month with the highest atmospheric pressure is January (30.16"Hg).
The month with the lowest atmospheric pressure is June (29.94"Hg).
Average wind speed in May
Alto Pass, IL
- Average wind speed in May: 7.3mph
The windiest month (with the highest average wind speed) is January (9mph).
The calmest month (with the lowest average wind speed) is August (5.6mph).
Average humidity in May
Alto Pass, IL
- Average humidity in May: 79%
The month with the highest relative humidity is May (79%).
The month with the lowest relative humidity is October (71%).
Average rainfall in May
Alto Pass, IL
- Average rainfall in May: 2.95"
The wettest month (with the highest rainfall) is April (3.31").
The driest month (with the least rainfall) is September (1.3").
Average rainfall days in May
Alto Pass, IL
- Average rainfall days in May: 14.9 days
The month with the highest number of rainy days is July (15.9 days).
The month with the least rainy days is January (8.4 days).
Average snowfall in May
Alto Pass, IL
- Average snowfall in May: 0"
The month with the highest snowfall is February (1.89").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in May
Alto Pass, IL
- Average snowfall days in May: 0 days
The month with the highest number of snowfall days is January (4.6 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
Alto Pass, IL
- Average daylight in May: 14h and 12min
The month with the longest days is June (Average daylight: 14h and 42min).
The month with the shortest days is December (Average daylight: 9h and 36min).
- Average sunshine in May: 9h and 6min
The month with the most sunshine is July (Average sunshine: 10h and 24min).
The months with the least sunshine are January and February (Average sunshine: 4h and 36min).
Average sunshine days in May
Alto Pass, IL
- Average sunshine days in May: 13.8 days
The month with the most sunshine days is October (21 days).
The month with the least sunshine days is July (12.8 days).
Average UV index in May
Alto Pass, IL
- Average UV index in May: 6
The months with the highest UV index are May, June, July and August (UV index 6).
The months with the lowest UV index are January, February and December (UV index 2).
Average cloud cover in May
Alto Pass, IL
- Average cloud cover in May: 40
The month with the most cloud cover is February (Cloud cover 51).
The month with the least cloud cover is September (Cloud cover 28).
Average visibility in May
Alto Pass, IL
- Average visibility in May: 6mi
The months with the highest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
The months with the lowest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).





