Thousands of 'No Kings Day' protests are expected to take place across the nation Saturday, with the 'flagship' protest planned for Philadelphia.

PHILADELPHIA — Cities large and small were preparing for major demonstrations Saturday across the U.S. against President Donald Trump, as officials urge calm, National Guard troops mobilize and Trump attends a military parade in Washington to mark the Army’s 250th anniversary.

Thousands are expected to pack the parkway for the "No Kings" protest. Organizers said they believe Philadelphia's demonstration will be among the largest in the country.

In a city known as the cradle of American democracy, an impassioned, hourslong protest filled the streets for a ‘No Kings Nationwide Day of Defiance.’

Philadelphia will be the site of a “flagship protest” in a nationwide movement opposing President Donald Trump’s Administration on the same day as a major military parade in Washington. The demonstration is expected to disrupt traffic throughout the day.

A flagship "No Kings" march and rally are planned in Philadelphia, but no events are scheduled to take place in Washington, D.C., where the military parade will take place on Trump's 79th birthday. Organizers of the protests say they want to take attention away from the parade.

Much of the central and eastern parts of the U.S. will experience rain showers and scattered thunderstorms, forecasters said.

Rachel Maddow reports on the planning of a massive protest event called "No Kings" scheduled for Saturday, June 14th, overshadowing Donald Trump's theatrical military parade, and marking a new peak in anti-Trump activism.