Northern Illinois hasn’t experienced its hottest summer on record, but Illinois already leads the nation with 178 tornadoes this year, while wildfire smoke, dangerous humidity and repeated severe storms have made 2026 one of the state’s most memorable weather years.

The region already has experienced swings from dangerous storms and heavy rains to intense heat waves and, most recently, air quality alerts from smoke from Canadian wildfires.

But has this summer really been unique in its intense weather patterns, and what can we expect next?

While this summer has featured plenty of sweltering temperatures, northern Illinois has experienced hotter summers.

“We typically see, at least every summer, a couple of heat waves where the heat index is over 100 degrees,” National Weather Service meteorologist Zachary Yack said. “That’s just typical here in the Chicago area. So far this summer, we had the one really big heat wave. That’s the one that happened in late June, early July.”

On June 29 and 30 and July 1, the heat index surpassed 100 degrees, Yack said.

The region experienced the hottest summer on record in 2020, when the average temperature from June through August was 76.7 degrees, edging out 1955’s record of 76.4 degrees.

The National Weather Service’s forecast calls for temperatures to be back in the 90s by Sunday.

“We’re still in the thick of summer here,” Yack said. “I wouldn’t expect anything drastically cooler until maybe until sometime in September or October.”

And there’s a reason why, when the sun sets following an extremely hot day, it doesn’t feel like it has cooled off that much.

“Humidity that is increasing during these extreme heat events can depress by a little bit the daytime high temperature but really increase the nighttime high temperature,” Illinois State Climatologist Trent Ford said.

“We see that nighttime temperatures have increased at a larger and a faster rate than daytime temperatures as a response to that humidity,” he said. “At night is when we expect to be able to recover from the daytime heat. And if our nighttime temperatures aren’t cooling as effectively as they were decades ago, it puts people at a higher risk for kind of that cumulative heat stress.”

Effect of El Niño

El Niño also could have contributed to the stormy weather Illinois has experienced so far this year. El Niño is a natural climate cycle that occurs when winds shift, and ocean waters near the equator become unusually hot.

Illinois leads the nation with 178 tornadoes so far this year, according to the National Weather Service. That’s more than three times the typical number of tornadoes – 54 on average – Illinois experiences annually.

Kankakee County has seen its fair share of stormy weather this year, including being hit by an EF-3 tornado and a hailstorm on March 10 that caused widespread damage.

“That’s the hot spot right now, unfortunately,” Ford said. “It’s bad luck, really. It kind of stinks that you have to chalk it up to bad luck, but that’s the way it’s been this year. The storms that have moved across the northern part of the state have made it so that it’s sort of a hot spot, northern to central Illinois.”

The areas that are hit the hardest by a storm are “essentially random,” Ford said.

“The fact that it’s been Kankakee this year is just bad luck,” he said. “It could have very easily been Tinley Park or Pontiac.”

Yack said El Niño’s effect on the weather patterns is not as noticeable in the summertime.

“The impact of El Niño on our weather in the summertime is kind of hard to determine because the jet stream is usually so far removed from us,” he said. “It usually doesn’t have the biggest impact what we see weather wise.”

Global warming here to stay

Ford believes people need to get used to summers being hot as a direct result of global warming.

“There is a lot of evidence that the trend in increasing heat is connected to global warming and to overall climate change,” he said.

To what degree global warming has in producing severe weather like tornadoes is a little less consistent, Ford said.

“It’s hard to identify trends in severe weather and then to associate those trends with something on a larger scale like global warming,” he said.

There is some evidence that climate change “may be a factor in increasing the frequency of tornadoes, especially those tornado outbreaks,” Ford said.

“There’s a lot more work that needs to be done to say how much of this potential increase in the frequency of tornadoes in the Midwest and in Illinois in particular is due to climate change and therefore how much we should expect into the future,” he said.

Illinois now receives about five inches more precipitation annually than it did a century ago, and heavy downpours have become about 40% more common, according to the Illinois State Climatologist’s office.

Precipitation also has gotten more intense, as the number of 2-inch rain days in Illinois has increased by 40% since the beginning of the 20th century

Mild winter predicted

Although it’s still too early to predict what fall will bring, temperatures are expected to drop to a more normal level by September.

“The initial outlook for kind of the August through October time period shows the best chances of near normal temperatures,” Ford said. “And when we get to September, October and November, we see the same kind of thing. I think that part of that is related to historical trends during El Niño years. When we have an El Niño in place, historically what we’ve seen in some El Niño years is a tendency for a cooler start to fall.”

A mild winter could follow, he said.

“In general, El Niño can have a larger effect on weather when it is stronger,” Ford said. “If that’s the case, the biggest impact and the clearest signal for El Niño in the Midwest is a warmer-than-normal winter.”

In addition, the region will likely see less snowfall, he said. Ford noted that winter is warming in Illinois at a faster rate than summer is.

According to climate monitoring data from the NOAA Centers for Environmental Information, over the past 120 years, winter and spring temperatures in Illinois have increased by two to three degrees.

“Combine that with El Niño that normally makes winter warmer, you get a really strong indication of a warmer winter for us here coming up,” Ford said.