A heat advisory in the Chicago area has been lifted, but a new threat of severe weather will arrive ahead of a sharp drop in temperatures.
According to the Storm Prediction Centre, the entire Chicago area faces a moderate chance of severe storms on Tuesday, with the major hazards being heavy rain and gusty winds as a slow-moving low-pressure system continues to drift across the upper Midwest.
With that system coming, temperatures will remain in the low 90s, with heat indices near 100, providing ample fuel for any storms that form during the afternoon and nighttime hours.
The forecast for Wednesday is expected to bring more showers and storms, although the SPC does not currently predict severe weather in the Chicago area during the day. Heavy rain may fall at times, but the greater risk will be several rounds of rain over the same locations, which might cause localised floods.
The Wednesday forecast predicts colder temperatures, with highs only reaching the upper 70s or low 80s during the day. Winds will change to the north as the low-pressure system approaches, helping to push it out of the area and cooling temperatures behind it.
Long-range prediction models predict that Thursday will mark the beginning of a period of calm weather in the Chicago area, with highs in the mid-to-upper 70s likely for many days.
Temperatures may rise somewhat during the next week, but they will most certainly remain near seasonal averages, in the low 80s.
