(NEW YORK) -- As the U.S.'s intensifying heat wave continues into the weekend, triathlons in the Northeast scheduled for Sunday were postponed and shortened.
The Boston Triathlon postponed its race to Aug. 21, while the New York City Triathlon shortened its bike and run courses for Sunday's triathlon and duathlon races.
Michael O'Neil, the Boston race's director, told ABC News the decision was made in coordination with the city and state due to the "current historic weather conditions."
"We take the health of our athletes, volunteers and spectators seriously. Boston does not compromise on safety or athlete experience. Due to the oppressive heat and humidity that could cause serious health concerns while competing this weekend, we worked together with the City of Boston and State of Massachusetts to postpone the race until August. Everyone should stay safe and hydrate as much as possible this weekend," O'Neil said in a statement.
Meanwhile, record high temperatures and excessive heat are expected to hit the Northeast with possible record high temperatures in Boston reaching 97 degrees and in New York City reaching 98 degrees on Sunday.
"With temperatures expected to reach the mid-90s this Sunday, in collaboration with local officials and meteorologists, we have made the difficult decision to shorten the run and bike portions of the NYC Triathlon and Duathlon. The safety of our athletes and everyone in attendance is our top priority," the triathlon said in a statement.
The New York City bike course will be shortened from 40 kilometers, or 24.8 miles, to 20 kilometers, or 12.4 miles. The course's north turnaround will now be at 181st Street and the West Side Highway.
New York's run race course will be reduced from 6.2 miles to 2.5 miles. The first leg of the duathlon run will be reduced from 2 miles to 1 mile and the second leg will be reduced from 6.2 miles to 2.5 miles. The course's south turnaround will be around 90th Street and West Side Highway.
"While it is disappointing to reduce the length of both races, our number one priority is to do all we can to ensure the safety and wellbeing of our competitors, volunteers, medical personnel and spectators," the triathlon said in a statement on its website.
This will be the twentieth running of the New York City Triathlon and its first-ever official duathlon.
The New York City Triathlon strongly encouraged its athletes to maintain hydration before, during and after races.
There will be touchless aid stations within the transition and at miles 0.9, 1.9 and along the run course. There will be medical support and toilets at each aid station and ice towels will be handed out at the finish line.
ABC News' Max Golembo contributed to this report.