Chicago Weather Today: Severe Storms and Sudden Temperature Drop—Full Hour-by-Hour Forecast

Chicago residents waking up on Saturday, July 19, 2025, should brace for another round of volatile skies. The National Weather Service reports scattered thunderstorms moving across Cook County through the late afternoon, with the heaviest cells timed for the early evening commute. Expect muggy highs near 81 °F and a heat index that could briefly touch the upper 80s. Gusty southwest winds around 15 mph will accompany the storms, and isolated downpours may trigger brief ponding on low-lying streets. Sunday brings a distinct change: a northeasterly wind off Lake Michigan ushers in cooler, wetter air. Daytime temperatures tumble to the low 70s while widespread rain—occasionally heavy—persists through midday, making indoor plans the safer bet. The wet weekend sets the stage for a classic Midwestern weather whiplash. High pressure builds Monday, delivering mostly sunny skies and pleasant highs in the upper 70s. By Tuesday and Wednesday, a broad ridge expands from the Plains, sending Chicago temperatures surging toward 90 °F. Afternoon heat indices could flirt with the mid-90s, especially south and west of the Loop. Keep an eye on vulnerable groups and plan extra water breaks if you work or exercise outside. Looking farther ahead, long-range models hint at another round of strong to severe thunderstorms late Thursday into Friday as a cold front crashes into the building heat dome. Early indicators point to damaging winds and torrential rain as the primary hazards, but hail can’t be ruled out. Beachgoers should note that persistent onshore flow Sunday may generate moderate to high swim risk, with rip currents possible at city and suburban beaches. Always obey the color-coded flag system and swim near lifeguards. Travel & commuting tips this week: • Saturday PM: Allow extra time on the Kennedy, Eisenhower, and Dan Ryan during downpours; hydroplaning risk peaks near underpasses. • Sunday CTA & Metra riders: Pack rain gear—lightning delays are possible. • Midweek heat: Pace long walks between shaded spots, choose early-morning jogs, and never leave pets or children in parked cars. Key takeaways for Chicago weather watchers: expect storms and steamy air today, a raw and rainy Sunday, picture-perfect July sunshine on Monday, and a shot at the summer’s hottest stretch by mid-week. Bookmark this page for continuous updates, and enable severe weather alerts on your smartphone to stay ahead of rapidly changing conditions.