Record US heat disrupts July Fourth celebrations and forces shutdown in Washington

Extreme heat has disrupted Independence Day celebrations across several parts of the United States, as record temperatures grip the East Coast and Midwest during the holiday weekend.

Organisers in Washington, D.C., cancelled a parade planned for the festivities. In the nation's capital, the Great American State Fair — staged as part of events marking America's 250th birthday — was temporarily shut down after multiple people required treatment for heat-related illnesses.

More than 165 million people faced sweltering conditions on Friday under record-breaking temperatures, according to the US National Weather Service. The agency reported that the heatwave stretched across the US East Coast and Midwest, placing a vast share of the population under dangerous warmth as the country observed the Fourth of July.

The severe weather is complicating plans for the long holiday weekend. Communities from the Atlantic seaboard through the Midwest are attempting to hold public gatherings even as outdoor events grow harder to manage safely.

The disruption at the Washington fair shows how quickly large open-air programmes can become hazardous when temperatures climb to historic levels. Authorities closed the site only after attendees at the capital gathering, tied to the country's 250th birthday commemorations, were treated for illnesses linked to the heat.

National Weather Service figures point to a weather event of unusual scale. With more than 165 million residents affected on Friday alone, the heatwave is shadowing Independence Day observances across a broad swath of the country rather than a single city or state.

Political and sporting calendars are also running into the extreme conditions. President Donald Trump is hosting a celebration marking America's 250th anniversary, while multiple World Cup matches scheduled to take place outdoors face added pressure as organisers weigh safety against the timing of the holiday weekend.