Smoke from Canadian wildfires has blanketed much of the northeastern United States, triggering health alerts, but a cold front expected on the weekend will help dissipate the dangerous haze in time for Sunday's World Cup final in the New York area.
If hazy and hot conditions remain until Sunday, however, they could prove challenging for players in the final, experts said.
More than 80,000 people are expected to attend the World Cup final between holders Argentina and European champions Spain at the open-air New York-New Jersey stadium while another 50,000 are expected to watch the game from Central Park in Manhattan.
New York City began feeling the effects of the wildfires this week and local authorities issued an alert, urging residents to reduce strenuous outdoor activity and take extra breaks if they are outside.
On Thursday the air quality in New Jersey, site of the stadium, was rated as 'unhealthy for sensitive groups' by several air quality measurement platforms.
"The areas where the smoke is the densest can actually cause respiratory problems. So those who may be a little bit more sensitive or may have respiratory issues may want to stay inside for as long as possible," AccuWeather meteorologist Alex DaSilva told Reuters in an interview.
"It's going to rain a lot on Saturday, so that should dissipate a lot of the smoke. Sunday morning, I think we're going to be seeing a cold front come through the area and it should kick out any remaining smoke that we're seeing."
New York Governor Kathy Hochul said on Thursday the smoke was creating unhealthy air conditions across the state and urged people to stay indoors.
Wildfire smoke from northern Canada has been a common summer occurrence across wide swaths of the United States in recent years.
But footballers, playing in Sunday's conditions, could still face health risks and would require considerable hydration and cooling, an expert said.
"It not only is going to be terrible, terrible air quality. It's hot, and that can cause an extreme amount of stress on the heart," said Dr Vin Gupta, a pulmonologist and board of directors member at the American Lung Association.
"That is a very powerful and dangerous one-two punch to the human body. It's going to be critical to maintain core body temperatures as low as possible."
Gupta, who said there was a need for more than just the two hydration breaks in every game in order to keep players safe, also suggested that fans with health issues wear masks in the stadium or even consider selling their tickets.
"If you're immunocompromised for whatever reason, consider watching the game at home instead of going in person. So sell your tickets if that's an option if air quality is going to be bad on Sunday," he said.
DaSilva said while spectators should try to limit their outdoor activities as much as possible on the day before the final, any risk would be lower by the time the match kicks off at 1500 Eastern time (1900 GMT) on Sunday.
"We are going to be seeing some of that smoke moving out of the area as we go into the weekend," he added.
