Heavy rains in May caused flooding in some parts of Illinois
The statewide average precipitation for May in Illinois was 4.52 inches, just 0.08 of an inch below normal.
However, heavy rains struck parts of Illinois, causing flooding. Some areas received up to 10 inches of precipitation by the end of the month, according to Illinois state climatologist Jim Angel at the Illinois State Water Survey, University of Illinois at Urbana-Champaign. Areas from Chicago westward, most of far Southern Illinois and McLean County received 5 to 9 inches of precipitation.
A few locations received more than 9 inches, including Countryside (Cook County) with 10.56 inches, West Aurora with 9.32 inches and Aurora with 9.27 inches.
The average temperature in Illinois for May was 62.2 degrees, just 0.5 of a degree below normal. This broke an eightmonth streak of abovenormal temperatures in Illinois.
Underneath the benign numbers were some stretches of cold weather at the beginning and middle of the month before summer-like conditions arrived in the last 10 days of the month. In the end, the warm and cold weather canceled each other out.
The National Oceanic and Atmospheric Administration’s Storm Prediction Center reported five tornadoes in Illinois in May, as well as 35 hail and 86 wind damage reports.
Local Conditions
The high temperature for the month of May in Union County was 91 degrees, which was recorded on May 30. The average high for the month was 76. The temperatures were recorded by weather observer Dana Cross of Jonesboro.
The low for the month was 38, which was recorded on May 15. The average low was 53. During the month, precipitation totalled 8.39 inches. The most rain in a 24-hour period was 3.07 inches, recorded on May 26.
Unseasonably Cool
The National Weather Service at Paducah reported unseasonably cool temperatures during May in the region.
In Paducah, a record low of 43 was tied on May 14. A record cold high of 63 was tied on May 16. A record cold high of 59 was set on May 17.
In Cape Girardeau, a record low of 41 was set on May 15. A record cold high of 59 was tied on May 16. A record cold high of 56 was set on May 17.
Heavy rainfall also was recorded in Cape Girardeau during May. The fourth highest daily rainfall for the month of May was measured, with 3.69 inches of rain on May 26.