CHICAGO, Ill (AP) – A Chicago road race that’s seen rain and snow in the past few years had tens of thousands of runners sweating in the heat.

More than 30,000 people participated in the annual Bank of America Shamrock Shuffle 8K Sunday morning. By noon the temperature was in the high 70s. That’s the warmest day in Chicago this year.

Meteorologists say the high on Sunday was 88 degrees.

The 4.97-mile run closed several streets and reroute bus stops around the Loop. It started and finished in Chicago’s Grant Park.

Three people were hospitalized for undisclosed injuries.

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