ADRIANA LIMA The Bikini Heat Is On

For once in her life, Victoria's Secret supermodel Adriana Lima did not look smokin' hot in lingerie ... because she was too busy looking smokin' hot in a bikini.

The gorgeous 31-year-old mother of two showcased her flawless golden mamacita curves by modeling a bunch of tiny sexy two-piece swimsuits for a photo shoot in St. Barts on Wednesday.

While temperatures have been hovering around the mid 80s ... we hear there is a scorching Brazilian front (and back) moving across the Caribbean island.