Thunderstorms | Can’t Sleep? Learn the Science of Storms

In the United States, a thunderstorm is classed as severe if winds reach at least 58 miles per hour, hail is one inch in diameter or larger, or if funnel clouds or tornadoes are reported. At any given moment, roughly 2,000 thunderstorms are happening somewhere on Earth, and Kampala and Tororo in Uganda, Singapore, and Bogor on Java all claim the title of the most thunderous place on the planet. This episode of I Can’t Sleep walks through the full life cycle of these storms—how they form, why they organize into different types, and what makes the difference between a harmless summer shower and a rotating supercell that spawns tornadoes.

The Recipe: Moisture, Instability, and a Lift

Every thunderstorm begins with the same basic ingredients. Warm air is less dense than cool air, so when a parcel of moist air gets warmer than its surroundings, it rises. As it ascends, it cools, and at its dew point temperature, water vapor condenses into liquid droplets or ice. This condensation releases latent heat, which further warms the rising air, making it even more buoyant and accelerating the updraft. This self-reinforcing cycle is called convection.