All, esp. meteorologists,

It's tornado season in the Southern States, hurricane season in the Carribbean and here in the Uk some sultry weather has lead to massive thunder storms. The usual explantion for what is powering this severe weather is that the latent heat of water vapour in the atmosphere is 'released' as the water condenses. OK, so far.

But how does it work? Water vapour can be condensed by cooling it, but that requires removal of energy from the system. It will also condense if the pressure falls, but that also occurs only if energy is removed. Condensation neither adds nor subtracts from the system's energy total, but how does it 'release' energy to build tornados, hurricanes or thunderstorms?

John