Memorial Day weekend is hot on the horizon, signifying the opening of public swimming pools across the country as well as the ushering in of a full season of beach and lake days. But it's not truly summertime until the girls start breaking out their bikinis, and Carrie Underwood indicates that time is now.

The country music superstar posted a photo of herself on Instagram on Friday (May 18) sporting a black bikini courtesy of her own fitness/lifestyle brand Calia by Carrie. "Summer vibes," Underwood writes with the photo, and it's an apt caption. She's posed relaxing by a swimming pool with a pareo tied around her waist, and looks ready to cool off in the water any minute.

The weather (and Underwood's wardrobe) isn't the only thing heating up this time of year. Underwood's latest tune, "Cry Pretty," is gaining rapid steam as the first song from her's next studio album, her first in nearly three years and her first on UMG Nashville after a post-Idol career spent on Sony Music Nashville. The album is also called Cry Pretty and will be released on Sept.14.

Underwood seems to be rebuilding her public presence following a hard fall at her Nashville-area home last year that left her bruised and broken. She says a "lone step" caused her to fall down some steps, breaking her wrist on impact. She also suffered facial injuries and underwent repair surgery which included 40-50 stitches.

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