(1.) Why do you think non-severe thunderstorms have such
a short lifetime (~1/2 hour)?
(A.) Raindrops which are produced eventually drag air downward shutting
off the updraft.
(B.) Raindrops can't stay up longer than 1/2 hour.
(C.) After 1/2 hour cloud shadows can't inhibit updrafts.
(2.) What parts of a non-severe thunderstorm could
be changed in order that the system be transformed into a severe thunderstorm?
(A.) Arrange the downdrafts so they do not fall back into the updrafts.
(B.) Eliminate the anvil to reduce shadows at
(C.) Seed the cloud to produce more, but
(3.) What atmosphere conditions would
you add to extend the lifetime of
(A.) Larger raindrops therefore strengthening the downdraft.
(B.) More moisture in the atmosphere.
(C.) Wind speeds which increase with height.