Fourth of July weekend is heating up!
The 37-year-old reality star has been soaking up the sun in Miami, Florida, taking to Snapchat on Saturday to give fans a glimpse of her toned booty.
WATCH: Kourtney Kardashian Shows Off Rock-Hard Abs in Teeny Black Bikini
In the pic, the mother of three's backside, clad in a strappy black one-piece bathing suit, is in full focus as she chats with her pal, nightclub owner David Grutman, while relaxing on the beach.
Kardashian also shared a group pic to Instagram, simply captioning it, "Beach dayz."
WATCH: Scott Disick Shades Kourtney Kardashian Over Justin Bieber Hookup Rumors
At one point, Kardashian, Grutman and another one of their pals enjoyed some "barefoot shopping."
One night earlier, Kourtney was spotted at Komodo, a local high-end Southeast Asian restaurant, to help kick off Grutman's 36th birthday festivities. They continued their celebrations at STORY nightclub, where Kourtney assisted DJ Cedric Gervais on the turntables.
In typical Kardashian fashion, the brunette beauty documented the night over social media, including a mirror selfie taken with BFF Larsa Pippen and a few of their other friends. Check out that tiger-printed dress!
Grutman later shared a pic from their outing to his own Instagram account, writing, "What a night. Thank You so much to everyone that made it so special for me."
WATCH: Justin Bieber Says He Still Had a 'Great Show' Despite Falling Off Stage in Canada
Saturday night, Kardashian and her crew are expected to attend
Justin Bieber's concert at the American Airlines Arena.
As we patiently wait to see pics and videos from the 22-year-old popstar's performance, watch the video below to see what happened when he took the stage in Saskatchewan, Canada, last month!
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