Jun 19 | Climate Review and Weather Update
by Trent Ford, State Climatologist
ISWS PRI University of Illinois
Our record breaking severe weather year rolled on this week. Temperatures were mild for mid-June, ranging from the mid-60s in northern Illinois to the mid-70s in southern Illinois, between 1 and 3 degrees below normal. A couple of the more impressive nighttime low temperatures this week included 45 degrees in Danville and 47 in Lisle. Despite the recent cooldown, June to date has been 1 to 3 degrees warmer than normal so far.
The big weather story yet again this week was severe weather in all forms. Multiple rounds of strong storms moved through the state mid-week, bringing multiple strong tornadoes, very strong winds, and some isolated pockets of hail. Among the more significant severe weather was an EF2 rated tornado that caused widespread damage to homes, businesses and uprooted trees and utility poles in Charleston and surrounding communities. Another, yet unrated tornado moved through the northern edge of Effingham, causing significant damage to homes and businesses. These tornadoes added to a remarkable string of frequent severe weather. Ahead of Wednesday’s storms, Illinois already had 138 tornadoes in 2026, only 4 away from the record high year of 2024. This isn’t really a record we like to break, especially twice in three years. Meanwhile, heavy rain pummeled parts of central Illinois, pushing several streams over flood stage. As of Friday morning, most stretches of the Illinois River were above flood stage, including moderate flood at Havana, with an expected crest early next week. Precipitation totals this week ranged from less than a quarter of an inch in south-central Illinois to nearly 6 inches in parts of western Illinois. June to date has been 2 to 5 inches wetter than normal in much of the state north of Interstate 72, and 1 to 2 inches drier than normal in much of southern Illinois. This month is already a top 10 wettest on record in Galesburg.
Looking ahead, there’s more good news and bad news. The good news is that temperatures next week will remain mild, with highs in the high 70s and low 80s. The latest outlooks from the Climate Prediction Center also show best chances of below average temperatures for the rest of the month and the entire month of July. Next week looks to continue our very wet streak, with 7-day precipitation totals forecasted to breach 1.5 inches across the entire state with pockets of potentially up to 3 inches. This additional rain will not be welcome in central Illinois, but will help with some drier conditions in parts of southern Illinois. We could see some severe weather on Sunday, but still a lot is uncertain about timing and location. So, once again please stay weather aware this weekend.