The Chicago Triathlon canceled its swim portion Sunday due to “unfavorable” beach conditions.

The National Weather Service issued a beach hazard statement for Lake, northern Cook and Central Cook counties, warning of waves of 3 to 6 feet and “life-threatening currents” that can lead to unsafe swimming conditions. The weather service recommends staying out of the water and not going to piers, breakwalls or other shoreline structures.

The warning is in effect until 3 p.m., well past the start time for the swim portion of the triathlon. The swim portion was also canceled in 2019 due to unsafe conditions.

Instead of swimming, participants can compete in the duathlon — or run-bike-run option — beginning at the swim start area on the lakefront path next to DuSable Lake Shore Drive and Balbo Avenue, according to organizers. Runners will then go 0.75 miles north to the transition area to grab their bikes, before heading to their respective courses.

The international distance participants were set to start at about 6 a.m., with the sprint distance participants beginning at 8:10 a.m.

Thousands of athletes will compete in Sunday’s duathlon, normally a 0.93-mile swim, a 24.8-mile bike and a 6.2-mile run, with the sprint roughly half that. The bike portion of the race shuts down Lower Wacker and southbound lanes of DuSable Lake Shore Drive. Free trolleys will circle Grant Park offering some of the best vantage points for the race.