Chicago Weather: Patchy Fog Overnight

CHICAGO (CBS) -- High pressure carved out clear skies Thursday afternoon into the night.

Patchy fog is possible after midnight until sunrise.

There will be lots of sun on Friday with highs around 90.

Saturday is the hottest day with highs in the mid-90s and a heat index of 100-105 degrees.

Expect gusty storms late Saturday night that may linger into Sunday. That may keep daytime highs in the upper 80s, near 90.