Exhaled Droplets Grow in Size on Cool Days May 21, 2021• Physics 14, 78 C. S. Ng Cough comparison. Simulations of a cough at two ambient temperatures: 1 ∘ C (bottom)—see videos below. A plume of vapor-filled air surrounding the droplets has higher humidity (white) at the colder temperature, causing the droplets to grow. This initial growth allows droplets to survive in the air for a longer time before evaporating, compared with those in the 3 1 ∘ C (bottom)—see videos below. A plume of vapor-filled air surrounding the droplets has higher humidity (white) at the colder temperature, causing the droplets to g... Show more C. S. Ng