Was a documentary on five Monday night, about severe storms, which touched on an idea to seed rain clouds with a polymer which soaks up water very rapidly. Apparently they tried it out on a small shower cloud with some success. They claim it could be used on hurricanes in future.
But this is all very dubious, the Americans tried cloud and hurricane seeding as long ago as the 1960s.
Meddline with weather systems also raises a big ethical issue. Stop rains in one place, they fall in another. Nature produces occasional disasters, but on the whole we live under a system which is globally benign. As a planet, we need sun and rain and wind and so on to keep on doing their bit. And we mess around with it at our peril.