Washington braces for massive July 4 celebration amid unprecedented security, record heat and fireworks pollution warning

Washington, D.C. — With more than 150,000 people expected in the capital for July 4, officials and federal agencies are preparing an unusually large security operation even as record heat and a Park Service memo raise public-safety and air-quality concerns, CBS News correspondent Natalie Brand reported.

Brand said the holiday has been designated "a national special security event coordinated by Secret Service," an escalation in federal coordination for Independence Day. The report said the U.S. Marshals Service swore in officers from 44 state and local agencies to assist in Washington and that thousands of National Guard and local law-enforcement personnel will be involved in securing large crowds around the National Mall.

President Trump is scheduled to travel to Mount Rushmore for a separate July 4 event. The report quoted President Trump saying, "It's going to be approximately 107 degrees out, and I'm going to go and I'm going to make a really long speech," comments that underscored public-health anxieties tied to extreme temperatures.

Record heat has already affected activities: the Great American State Fair temporarily closed because of dangerous temperatures, and the segment relayed common-sense safety guidance — electrolytes, drinking water and seeking shade — for people attending outdoor events.

A record fireworks show is planned over Washington, with more than 860,000 pyrotechnic effects reported. The Washington Post, the program said, obtained a Park Service memo warning that the volume of fireworks could create air-pollution problems that people should avoid. The transcript does not record a response from the Park Service or an announcement of changes to the fireworks plan.

The combined factors — large crowds, expanded federal security operations, extreme heat and a memo about potential air-quality effects from an unusually large fireworks display — frame the public-safety priorities for the holiday in the capital. CBS News coverage included on-the-ground visuals of flyover rehearsals that drew public interest.