Quantifying the Lucky Droplet Model for Rainfall

Abstract It is difficult to explain rainfall from ice-free clouds, because the timescale for onset of rain showers shorter than mean time collisions between microscopic water droplets. has been suggested that raindrops are produced very rare ‘lucky’ droplets, which undergo a large number on short compared first collision. This work uses deviation theory develop estimates shower, as function collision rate coefficients. The growth history fast-growing droplets do become discussed. shown their few always approximately equally spaced in time, regardless how varies collisions.