The 1995 Chicago Heatwave was a summer heat wave that resulted in hundreds of deaths. The temperatures averaged between the highs of 43 degree Celsius and the low's of 26 degree Celsius during night time.

Officially it's 105, set in 1995 during the infamous heat wave.

Unofficially it's 109, set in 1935.

I cannot explain what caused the heatwave, because i havent researched it yet, but the heatwave played a role in strengthening the Chicago community, and improving warning systems and procedures. In 1999, Chicago had another heatwave, and because of improved warning systems, only 110 people died (which was still a catastrophe), but was better than the outcome of the 1995 heatwave, which somewhere between 700 and 800 people died.

Yes most definately, one of the worst weather disasters in the history of the United States was the 1995 Chicago Heat Wave. The 1995 Chicago heat wave led to approximately 600 heat-related deaths over a period of five days. The temperatures soared to record highs in July with the hottest weather occurring from July 12 to July 16. The high of 106° F (41° C) on July 13th. A contributing factor to the heat wave is an effect called an urban heat island. Urban heat islands are caused by the concentration of buildings and pavement in urban areas, which tend to absorb more heat in the day and radiate less heat at night into their immediate surroundings than comparable rural sites. Therefore, built-up areas get hotter and stay hotter. This is an extreme example to answer your question but it is not totally uncommon to have a few days near or even above the 100 degree mark every other summer or so.

There was a major heat wave during the summer of 1995 in the Midwest. There were also several tornadoes in Wisconsin in 1995.