While summer has been mainly cooler than average, a late-season heat wave will start this weekend. According to the National Weather Service, daytime highs will climb into the mid-to-upper 90s beginning Saturday and continue for several days into the middle of next week. Heat index values in excess of 100 degrees will be common in the afternoon and evening hours daily. The hot temperatures may also impact some schools as classes begin on August 23rd and 24th locally. With several outdoor activities scheduled locally over the next several days and the Iowa State Fair continuing through Sunday, residents are reminded to stay hydrated and take frequent breaks in air conditioning. Stay tuned to KNIA/KRLS for updates, including for possible cancellations and delays.