Can humans really make it rain? What cloud seeding actually does — and can’t

Cloud seeding adds particles intended to help existing cloud droplets or ice crystals grow; it cannot create moisture or storm clouds from a clear sky. Results depend on suitable clouds, temperature, wind, and careful measurement, so a successful flight is not proof that every extra drop came from seeding. The technology may modestly influence precipitation under the right conditions, but it cannot end a major drought on command or precisely steer where rain falls.