Heat, Humidity To Dominate Until Storms Saturday Night

CHICAGO (CBS) -- Heat and humidity will dominate this first day of Lollapalooza, although a lake breeze will make conditions more tolerable.

CBS 2 Meteorologist Mary Kay Kleist reports it was already 89 degrees at O'Hare International Airport, 87 at the lake and 91 at Midway Airport as of 11:20 a.m. The winds were calm in the midday hours, but a lake breeze later in the day will cut the temperature to 86 in the city and 85 in Zion, while the high climbs to 93 in Joliet and Kankakee.

High pressure is now situated over region, keeping conditions clear and sunny. On Saturday, the hot air from the south will increase in intensity, with a high of 93 and a heat index making it feel like 105.

But a cold front coming in to the north weekend will bring storms – mainly in the evening – and with a slight risk of severe weather.

Following the storms, high for Sunday drops to 84, Monday 83, Tuesday back up to 87, Wednesday 85 and Thursday 86.