Organizers canceled two long-distance races scheduled for Sunday in Minnesota’s top two cities due to concerns about extreme and hazardous weather conditions caused by record high temperatures and humidity. The races were estimated to attract around 20,000 participants.

Twin Cities in Motion, the organizers of the Medtronic Twin Cities Marathon, had initially anticipated 8,000 participants for the event that spanned from Minneapolis to neighboring St. Paul. However, on Sunday, they made the decision to cancel the marathon as well as a 10-mile race that was set to attract 12,000 runners.

In a message sent to participants on Sunday morning, the organizers of the race stated that the most recent weather forecast predicts extreme heat conditions that would make it unsafe for runners, spectators, and volunteers to participate.

Prior to Sunday’s race, the organizers had cautioned about potential hazardous weather. Despite this, the race was scheduled to continue with extra safety measures in effect. However, on Sunday morning, a “black flag” warning was issued, resulting in the cancellation of the event.

The National Weather Service forecasted a peak temperature of 88 degrees Fahrenheit for Sunday afternoon.

A group of runners had gathered at the starting line of the race on Sunday morning and informed the Minneapolis Star Tribune that they intended to participate regardless.