Another sunny day in Chicago, clear skies for partial lunar eclipse Tuesday night

CHICAGO (CBS) — As our warm, dry weather pattern continues this week, we are becoming more confident that a weather pattern change this weekend may lead to soaking rain and cooler temperatures just as autumn begins.

Following patchy fog early Wednesday, another day of steady east-northeast winds will keep many areas cooler than recent days. High temperatures will still be above average, reaching the middle 80s under sunny skies. Wednesday will be Midway's 19-consecutive day without measurable rainfall -- a dry stretch that only occurs roughly once every four years.

Winds turn more southerly Thursday and Friday, boosting some neighborhood high temperatures to near 90 degrees.

This weekend, a storm from the western U.S. successfully breaks down the heat ridge overhead. Scattered thunderstorms look more likely on Sunday and Monday, and cooler air follows with more seasonable high temperatures in the 70s.