Scoop: Trump's late July 4 speech throws D.C. fireworks timing into flux

One big reason why D.C.'s July 4 fireworks show is being pushed later: President Trump is scheduled to give a 45-minute speech on a National Mall stage, a source involved in the planning tells Axios.

Why it matters: With temperatures expected to hit 102 and inauguration-level security on the Mall, every delay ripples through the evening, keeping people in the heat longer, slowing trips home and pushing bedtimes.

State of play: The Trump-allied Freedom 250 wants to break the Guinness World Record for largest fireworks display, firing 850,000 shells over 40 minutes.

Yes, but: Trump's penchant for rollicking speeches makes it hard to pinpoint when the show starts.

Trump is supposed to begin speaking at 9:50pm, according to a Secret Service official who wasn't able to go on the record because plans are, well, very much in flux.

"He could take a half hour, he could take" more, the official added.

Cabinet secretaries and Congress members will be in attendance for a speech Trump teased on social media over the weekend.

Adding to the made-for-TV flavor, Freedom 250 announced Tuesday that a military flyover will feature a "massive 17-aircraft formation" that debuts Air Force One, the Boeing 747-8 gifted by Qatar.

The intrigue: Mayor Muriel Bowser made news on Monday, saying that fireworks "won't begin until 11pm."

Freedom 250 continues to advertise 10:30pm on its website. The Secret Service official says 11pm was being considered as recently as last week.

"Planning is very fluid," they added. "The timeline is subject to change right up until the start of the event."

What we're watching: If thunderstorms strike, it could go even later, especially if attendees who passed through TSA-level security get evacuated from the Mall. There's a 30% chance for precipitation, per the National Weather Service.

A past-midnight, July 5 fireworks show isn't out of the realm of possibility, the official said.