Anybody rememember the "cloud-seeding" experiments from the late '50s and early '60s? Crystals of, I believe, silver iodide were dispersed into tropical systems in hopes that doing so would induce heavier rains and cause the storms to "rain themselves out". Worked about as well as the late '50s and early '60s other notable experiment, the Edsel. Heck, they both looked really good on the drawing board.