President Donald Trump's planned July Fourth extravaganza appeared to be moving forward as scheduled Thursday after a downpour soaked those who took the president's advice and arrived early.

"Weather looking good, clearing rapidly and temperatures going down fast," Trump tweeted early Thursday evening. "See you in 45 minutes, 6:30 to 7:00 P.M. at Lincoln Memorial!"

The White House released excerpts from Trump's planned speech just over an hour before he is set to deliver it in front of the Lincoln Memorial in Washington.

"We come together as one nation with this very special salute to America," Trump will say, according to his prepared remarks. "We celebrate our history, our people, and the heroes who proudly defend our flag — the brave men and women of the United States Military!"

"As long as we stay true to our cause — as long as we remember our great history — and as long as we never stop fighting for a better future — then there will be nothing that America cannot do," the president will say.

Though attendees were told that the event was delayed, Trump's speech is still slated to start at 6:30 p.m., according to the White House.

More rain and possible thunderstorms are in the forecast for the rest of the evening Thursday and could impact the event, where military demonstrations and Trump's remarks are the featured draw.

Trump promoted the evening event multiple times on Twitter, urging people to arrive ahead of time for "one of the biggest celebrations" in U.S. history event as meteorologists warned of possible downpours.

In early morning tweets, Trump previewed "large scale flyovers of the most modern and advanced aircraft anywhere in the World" over the Lincoln Memorial and teased that "perhaps even Air Force One will do a low & loud sprint over the crowd" ahead his speech.

"People are coming from far and wide to join us today and tonight for what is turning out to be one of the biggest celebrations in the history of our Country, SALUTE TO AMERICA," he said.

The military display will also include performances by The Old Guard Fife and Drum Corps, the U.S. Army Band, the Armed Forces Chorus, the U.S. Marine Corps Silent Drill Platoon and the U.S. Navy Blue Angels. Tanks are already in place near the Lincoln Memorial.

People are coming from far and wide to join us today and tonight for what is turning out to be one of the biggest celebrations in the history of our Country, SALUTE TO AMERICA, an all day event at the Lincoln Memorial, culminating with large scale flyovers of the most modern..... — Donald J. Trump (@realDonaldTrump) July 4, 2019

Hours ahead of the event's start, revelers and protesters were out and about despite the foul weather concerns.

The National Weather Service issued a flash flood watch active until 8 p.m. for parts of the nation's capital and the Maryland and Virginia suburbs, The Associated Press reported. According to the Weather Service, storms are expected in the early afternoon and there could be torrential rain with a chance of flash flooding.

Code Pink, an anti-war organization, had put up a 20-foot-tall diaper-clad balloon of an infant Donald Trump in the shadow of the Washington Monument, the AP reported — though the "Baby Trump" blimp was later deflated amid stormy weather. The group had not been allowed to inflate the balloon with helium, according The Washington Post, nor was it permitted to station the balloon in view of the Lincoln Memorial.

Trump supporter Kevin Malton, of Middlesboro, Kentucky, took pictures with the balloon before it deflated. He said he was glad to see the mix of political beliefs at the event.

People gather on the National Mall ahead of President Donald Trump's "Salute to America" Fourth of July event. Andrew Caballero-Reynolds / AFP - Getty Images

Code Pink co-director Medea Benjamin said the organization and its members "oppose the politicization of July Fourth by President Trump."

Democrats and other critics of the planned military demonstration have voiced similar concerns, saying that the president could turn the celebration of a national holiday into a campaign rally. Others, like retired Navy Admiral James Stavridis, have said they are worried about the appearance of politicizing the military.

"Whenever you kind of array the U.S. military as a backdrop, and then you make a speech in front of them, what everybody, every military person is hoping, is that that speech will not be political, will not be partisan, that it really will be a speech of unity and talk about patriotic values," Stavridis said on MSNBC Thursday morning.

While campaigning in Iowa on Thursday, 2020 candidate and former Vice President Joe Biden said he wondered what Trump will choose to focus on in his evening address.

"What, I wonder, will Donald Trump say this evening when he speaks to the nation at an event designed more to stroke his ego than celebrate American ideals?" Biden said. "Will he speak to the example America must set to inspire the world? Will he offer a robust defense of the democratic values that have always been our strength in times of crisis? We all know the answer to that. Donald Trump is incapable of celebrating what makes America great — because he doesn’t get it.

During a Nevada campaign event Wednesday, 2020 candidate Sen. Elizabeth Warren, D-Mass., said, "Donald Trump is handing out tickets to his big donors, that's a campaign event."

"And if he is going to do a campaign event, then it should be paid for by his campaign contributions. It should not be paid for by the American taxpayer," she added.

Two Trump campaign officials told NBC News Thursday that the "Salute to America" would not be documented for future campaign ads or video, calling it "entirely an official White House event."

Those officials acknowledged some campaign staff could be in attendance — off the clock.

"Some campaign staff may be attending as spectators because we received tickets as a courtesy, much like for the Easter Egg Roll or White House garden tours," one campaign official said, referring to annual traditions that take place at the White House.

Meanwhile, Trump's 2020 campaign communications director Tim Murtaugh dismissed complaints that the president is co-opting the Independence Day event for political purposes.

“President Trump loves this country. He’s not going to apologize for that," Murtaugh said.

A White House aide who has seen drafts of Trump's remarks said the speech will be “about the greatness of America" and argued that the message will not be political.

There have also been concerns about the cost of the event. According to The Washington Post, the National Park Service is diverting roughly $2.5 million in entrance and recreation fees from parks around the county to cover the tab for Trump's event.

The diverted fees, however, represent just a fraction of the total cost, which remains unclear. In a tweet on Wednesday, Trump downplayed the cost, writing: “The cost of our great Salute to America tomorrow will be very little compared to what it is worth.

“We own the planes, we have the pilots, the airport is right next door (Andrews), all we need is the fuel. We own the tanks and all. Fireworks are donated by two of the greats. Nice!”

Sen. Bernie Sanders, I-Vt., another White House hopeful, contended Thursday that the money would be better spent elsewhere.

"I think we need money to go into affordable housing, I think we need money to go into rebuilding our infrastructure," Sanders said after he finished walking a parade route in Slater, Iowa. "I'm not quite sure we need money to go into put tanks in downtown Washington, D.C."