Marvin’s extended rooftop bar creates a large, comfortable spot to spend a lazy Sunday afternoon with good music, cheap drinks and a lively crowd. (Craig Hudson/For The Washington Post)

By the time Sunday afternoon rolls around, I often realize that I’m not ready for the weekend to end. Yes, I have to be back in the office in less than 24 hours. Yes, I probably should clean the bathroom and do some vacuuming.

On the other hand, the sun is shining and I didn’t suffer through that never-ending winter so that I could sit on my couch. I want to be outside, listening to good music, having a drink and hanging out with friends.

With that in mind, here are three Sunday parties that let you take advantage of the warm weather on a rooftop deck. As a bonus, all offer free admission and none require reservations.

Out on the Deck
With Keenan and Smudge

Lauren Cooper (center) celebrates her birthday with friends at Marvin on May 11, 2014. (Craig Hudson/For The Washington Post)

3 to 8 p.m. Marvin, 2007 14th St. 202-797-7171.

For the sixth straight year, DJs Keenan Orr and Lucas Smudge helm one of the most irresistible parties in Washington. Sunday afternoons at Marvin are always full of good-looking people sipping $4 mimosas, $5 Absolut Peppar bloody marys and $6 glasses of wine and rail drinks until the sun sets. The music is just as diverse as the crowd: Orr might drop DJ Jazzy Jeff and the Fresh Prince’s “Summertime” or A Tribe Called Quest’s “Electric Relaxation,” while Smudge’s playlist ranges from Public Enemy to ZZ Top.

The bearded Smudge, who looks like a member of a metal band, and the slight, stylish Orr appear to be the classic odd couple — “I’m the straight white DJ and he’s the gay black DJ,” Smudge jokes — but you can hear just how much fun they have playing off each other. They were first paired at the Rock and Roll Hotel in 2008 and have worked together since. Their primary gigs are elsewhere: Orr regularly spins at Cobalt, where the Washington Blade named him “Best DJ,” and in New York City; Smudge holds down the main room at Eighteenth Street Lounge on Saturday nights but also pops up at Velvet Lounge and Little Miss Whiskey’s.

When they get together on Sundays, magic happens. Their retro jams elicit some dancing, though most people are content to grab a seat, gab and flirt. The atmosphere is comfortable — the fall 2011 expansion that merged Marvin’s rooftop with the deck at the neighboring (since closed) Blackbyrd Warehouse turned a long, narrow space into a wide terrace with two large bars, twice as many seats and standing room to spare. Throw in affordable cocktails and a lively crowd, and you’ve got an upscale, enjoyable summer party.

Sundays at the Brixton

2 to 8 p.m. The Brixton, 901 U St. NW. 202-560-5045.

The new Sunday afternoon gatherings at the Brixton feel, in many ways, like the upstart younger sibling of Keenan and Smudge’s party. There are similarities: The bars share owners, their Sunday parties both feature a DJ spinning until 8 p.m., and each offers a number of happy hour specials. (The Brixton’s includes $5 drafts, rail drinks and vodka cocktails from 1 to 5 p.m.) But the crowd at the Brixton is younger and more energetic — on my last visit, I watched a group of women form a spirited dance circle to a remix of Beyonce’s “Run the World (Girls)” and Major Lazer vs. the BeatThiefs “Pon Di Beats Pon Di Thiefs,” and two guys joined them with a few moves of their own when Mike Will Made-It’s “23” started blasting from the speakers.

Despite DJ Eskimo’s pumping beats, the vibe is still more pub than club. Plenty of people relax with a gin and tonic or European beer along the iron railings that surround the Brixton’s roof, especially in the warm sunshine that floods the side of the building fronting U Street. It’s a nice spot for people-watching or checking out what’s going on across the street at Nellie’s Sports Bar, where the roof is being renovated. The rear half of the deck is calmer and a little less interesting, but it’s also covered, which comes in handy during one of Washington’s notorious passing summer showers.

If you’ve been to the Brixton on a Friday or Saturday night, you know there can be long waits to get in and get up to the roof. That’s not the case on Sunday afternoons.

Movies on the Roof

7 p.m. Rock and Roll Hotel, 1353 H St. NE. 202-388-7625.

The Rock and Roll Hotel’s rooftop deck opens at noon on Sundays; at brunch, bartenders sling “hangover hash” (corned beef, eggs and onions on a bed of tater tots) and pour rivers of bottomless mimosas to a rocking metal soundtrack. But things get more interesting later, when the sun begins to set and movies are projected onto an eight-foot screen on the wall.

The Movies on the Roof series, which began May 4, features two films every Sunday, beginning at 7 p.m. Each month will have a different theme: For May, it’s anime, so customers hanging out on the deck this Sunday will be treated to “Princess Mononoke” as the main feature, with a second film (starting about 9 p.m.) to be selected by audience vote. (Last week, the winner was the legendary “Akira.”) There will be horror movies in June, owner Fritz Wood says. After that, he’s considering a “Christmas in July” theme with classic ’80s holiday flicks.

While the movies play, there’s a special happy hour with $4 mixed drinks, $3 cans of Pabst Blue Ribbon and $1 off all other booze, plus free popcorn and half-price wings.

You might have guessed that this isn’t an Angelika Film Center Mosaic -level experience: The screen sags at one edge, the tables wobble and police helicopters occasionally rumble overhead. Just take it for what it is and enjoy; the sound is respectable and the sightlines aren’t bad if you don’t sit at the bar. And, come on: Free movies, free popcorn and cheap drinks are not a bad way to end your Sunday night. Just remember to set your alarm when you get home.