Re-shoot it...

You are too far away from any facial expressions that may show sweat or heat discomfort on anyone's face and the clouds make it look cold, not hot.

You and those people may have been hot, but no matter what you do to this print, your viewers will never know this simply because of the way you chose to shoot it.

This is an image that needs a more powerful human expression or moment to read as being "hot" and it simply does not have that at all.