Powerful thunderstorms swept sections of Kansas and Nebraska Tuesday. Diverging jet stream winds, expected to shift into Illinois later Wednesday and an indication that air is rising on a massive scale, helped prod those storms into existence late Tuesday. The 38,000 ft. tall storms unleashed tennis ball size hail on an area of Nebraska near Ainsworth.
Moderate humidities coupled with daytime heating, converging ground-level winds along an incoming front and strong jet stream winds overhead appear likely to lay the groundwork for possibly active clusters of thunderstorms later today into Wednesday night.
Unusually warm temperatures arrive later this weekend. Highs of 90° are possible Sunday, Monday and Tuesday. They would be the city’s first September 90s in three years. Four of ten years since 1928 have hosted 90s at Midway Airport beyond September 11.
WGN-TV Chief Meteorologist Tom Skilling and the WGN Weather Center staff provide daily coverage of weather in the Chicago area.
