It's hot out there, and Hollywood's sexiest ladies certainly aren't helping the global warming crisis.

From the star with the most enviable body, to the up-and-comer to watch, to a much-anticipated comeback, we're counting down summer 2012's hottest women of Hollywood in our HuffPost Heat Wave challenge.

So, how did these ladies make the cut? We painstakingly perused countless bikini photos, summer movie trailers, red carpets and checkout-lane headlines to narrow down our "Who's hottest?" pool.

Check out the contenders below and vote on who is the hottest summer siren below:

WHATWHOWHY?
THE BODYKate UptonWe've all seen her "cat daddy" in a microscopic bikini ... Enough said.
THE BLOCKBUSTER BEAUTYBlake LivelyBlake is heating up the box office in some racy new roles. The steamy trailer from her latest film, "Savages," no doubt had men behaving like the title to get a front row seat in the theater.
THE ULTIMATE SWEETHEARTEmma Stone"If Emma just got to know me, I really think we could be best friends." Does this thought sound familiar? Get in line.
THE ONE TO WATCHChloe MoretzThis kind of beauty at 15 years old should be illegal. But if Chloe can manage to avoid young Hollywood's pitfalls, she'll have directors wrapped around her finger for years to come.
THE HOT MAMAKourtney KardashianAnyone who can compete with sisters Kim and Khloe -- while pregnant! -- deserves top honors on this list.
THE SINGLE LADYKatie HolmesWithout Tom Cruise by her side, Katie is poised to make a comeback that none of us saw coming.
THE TRIPLE THREATJulianne HoughThis "Dancing with the Stars" alum may not be up for an Oscar anytime soon, but she's well on her way to becoming a serious triple threat.
THE COMEBACK KIDBritney SpearsIt's Britney, bitch. Britney's turn as an "X Factor" judge may not rival her post-shaved-head comeback, but still, no small feat.

Quick Poll

Who should reign victorious in our HuffPost Heat Wave Hottest Woman of the Summer contest?

VOTE

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  • Kate Upton

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  • Blake Lively

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  • Emma Stone

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  • Chloe Moretz

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  • Kourtney Kardashian

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  • Katie Holmes

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  • Julianne Hough

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  • Britney Spears

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