For those planning to attend the Folklife Festival, the parade, or the fireworks on Monday, District officials advise using Metro instead of trying to drive around the city.
Captain Bob Reese with the National Park Service also warns visitors to bring plenty of water.
"If you're thirsty, you're already dehydrated," he says. "So drink and when you don't want to drink anymore, drink some more. You should be drinking 16 to 32 ounces of water per hour when you have the conditions that we're going to have on the mall on Monday – high heat and high humidity."
Alcohol and personal fireworks are prohibited at the events. People should also expect their bags and coolers to be checked, and they should expect a lot of people as well. Organizers say the earlier you get to the Mall the better.