Though an excessive heat warning has been issued for Cook County this heat wave will not set any records. Highs will be in the lower 90s with heat indices around 100° While this is certainly hot it's nowhere near the killer heat wave of 1995 when the heat index hit an unbelievable 127°! The problem with this spell of hot weather is its longevity. While the max heat index will barely top 100° the overnight heat index will stay above 75°. The cumulative effect of the heat on the body can sneak up on you so make sure to take it easy especially during the afternoon. Don't forget to check on the elderly espcially those living in a home without air conditioning.
Cooler and drier air will start to return on Sunday so there is some relief on the way.