Latent heat - (n.)

The energy contained in water and in water vapor, relative to ice or water, respectively. When water vapor condenses, the latent heat is released, warming the surrounding air. This heat powers storms, including the great hurricanes. When water freezes, latent heat is also released, warming the air in contact with the forming ice. Latent heat plays an important role in the redistribution of heat on the surface of Earth, especially through evaporation in the tropics and subtropics and the subsequent precipitation in higher latitudes.