The World Cup final scheduled for Sunday in the New York-New Jersey area is under a cloud of uncertainty as dense wildfire smoke drifting south from Canada has triggered unhealthy air quality alerts across the United States.

On Friday, Washington DC was also hit hard, registering at the second-highest 'very unhealthy' level on the air quality index, prompting authorities to urge all residents to avoid unnecessary outdoor activity.

The final, expected to draw 80,000 fans at the open-air MetLife Stadium, is being closely monitored by FIFA and the White House task force. FIFA confirmed Friday that the smoke does not currently pose a threat to the match.

Detroit and Chicago recorded 'hazardous' air quality readings, with IQAir ranking them as the most polluted cities globally. The National Weather Service warned that smoke may thicken overnight into Saturday morning.

Meteorologists noted that winds over the Great Lakes could push more smoke into the northeastern US, though some improvement is expected by Sunday. However, the situation remains fluid.

Climate advocates linked the increasing frequency of wildfire smoke episodes to climate change, urging a rapid transition to clean energy. In Canada, over 200 fires were burning out of control, particularly in Ontario.

Source: www.aljazeera.com