Short answers, pulled from the story.
Thunderstorms form when warm, moist air rapidly rises, cools, and condenses into cumulonimbus clouds. A lifting force such as a weather front, shortwave trough, or terrain is required to accelerate the air upward. The storm requires moisture, an unstable air mass, and that lifting mechanism working together.
All thunderstorms pass through a developing stage, a mature stage, and a dissipation stage. Each stage takes an average of 30 minutes, and the average thunderstorm spans a diameter of 24 km. The mature stage is the most dangerous, marked by the simultaneous presence of updrafts and downdrafts.
A supercell is the strongest type of thunderstorm, characterized by a powerful rotating updraft called a mesocyclone and separate updraft and downdraft regions. Research has shown that at least 90 percent of supercells produce severe weather, including hailstones up to 10 cm in diameter, straight-line winds exceeding 130 km/h, and most of the tornadoes that occur on Earth.
A typical thunderstorm lifts approximately 500 million kilograms of water vapor and releases around 10 to the 15th power joules of energy when that vapor condenses. This is more energy than was released during the atomic bomb blast at Hiroshima, Japan, in 1945, and is on the same order of magnitude as a tropical cyclone.
Thunderstorms occur most frequently in tropical rainforest areas, where they can happen nearly daily. Kampala and Tororo in Uganda, and Bogor on the Indonesian island of Java, are among the most thunderstorm-prone places cited. At any given time, approximately 2,000 thunderstorms are active across the Earth.
Thunderstorm asthma is the triggering of an asthma attack by environmental conditions created by a local thunderstorm. During a storm, pollen grains absorb moisture and burst into much smaller fragments that wind disperses widely. Unlike larger pollen grains filtered by nasal hairs, these tiny fragments pass through and enter the lungs, provoking an asthma attack.