Meteorologists use the Lifted Index (LI) to estimate the atmosphere's potential to produce severe thunderstorms. The Lifted Index measures the temperature of rising air in the atmosphere to determine the likelihood of a thunderstorm. Satellite imagery is also used to track thunderstorms.
According to Weather Online, thunderstorms are formed when air parcels rise through the atmosphere after being heated by the sun. After the air rises, it begins to cool, which results in condensation and the formation of cumulus clouds. As the air continues to travel vertically, the cumulus cloud transforms into a cumulonimbus cloud. Cumulonimbus clouds are capable of producing strong winds, thunder, lightening, intense rain and tornadoes. They can reach heights of up to 20 kilometers above the Earth's surface.
There are two types of thunderstorms: air mass thunderstorms and severe thunderstorms. Air mass thunderstorms are the most common thunderstorms. They occur most commonly in the tropics where convectional heating of moist surface air occurs year-round. Severe thunderstorms occur less frequently than air mass thunderstorms, but often have severe weather associated with them. These types of thunderstorms are typically accompanied by very strong winds and frequent lightning. In some cases, a severe thunderstorm may also have a tornado or hailstones.