As the afternoon thunderstorms begin, precipitation falls from the condensed clouds and falls down to the ground. Sooner or later there is enough rain to start a run off of water down the hill into the nearby steam below. When the sun finally breaks throughout the clouds and the rain stops, the sun starts to evaporate the precipitation left in puddles and other areas of run off. Eventually the clouds will have enough condensation from the evaporated water to rain again and the cycle will repeat itself again.