Falling in a dream is very common. You wake with a start, before you hit the bottom. It is quite disconcerting and can re-occur over a long period of time. Falling in a dream indicates there is something that is not resolved in your life, or that you are running from. It will probably continue to recur until that matter is resolved.
Natural occurrences can mean a variety of things.
A volcano can symbolize emotions and generally indicate somebody with a quick temper. A fire represents sexual desire, and is generally seen as good luck particularly when at a home, which indicates a happy home. A fire at a place of business indicates prosperity. Lightening represents the advent of love in your life whereas a snowfall can indicate emotional distress. A snowstorm can represent extreme frustration, and if you are climbing a snow covered mountain you are probably having business disappointments.