temperature reading of 106 °F (41 °C) was recorded
on July 24, 1934, although an unofficial reading of 109 °F (43 °C)
was also recorded at Midway Airport during that month. The lowest temperature
of −27 °F (−33 °C) was recorded on January 20, 1985, at O'Hare
Airport. The city can experience extreme winter cold waves and summer heat
waves that may last for several consecutive days. There are also many mild
winter and summer days. Thunderstorms are not uncommon during the spring and
summer months which may sometimes produce hail, high winds, and tornadoes
