National Weather Service officials were expecting the haze and fog that has blanketed the area to dissipate in portions of north central and northeastern Illinois, and northwest Indiana, as scattered thunderstorms were expected to move into the area beginning Friday afternoon.
The storms could affect spectators planning to attend Saturday’s NASCAR event downtown.
Officials cautioned that a few storms moving through the area on Friday could be severe, mostly south of Interstate 80 with damaging wind and large hail. Other storms could affect the evening hours increasing after midnight, officials said.
Also, there was an excessive heat risk, as temperatures reached 88 degrees Friday afternoon at both Chicago’s airports.
Meteorologist were watching a front carrying severe thunderstorms and heavy rain moving east from the Central Plains to the Ohio Valley in the coming days. The strongest storms are expected to shift farther east and are expected the hit the Great Lakes by Sunday morning, officials said.
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Those watching the NASCAR event Saturday may have to deal with scattered thunderstorms after 4 p.m. A high of 79 degrees is expected with a 60 percent chance of rain.
There was a 70% chance of showers and thunderstorms between 7 p.m. Saturday and 1 a.m. Sunday, officials said.
Sunday, the forecast includes showers and possibly a thunderstorm, with a high near 72.
The forecast for the 4th of July holiday, Tuesday, was sunny with a high of 84. A chance of showers returns Wednesday.