Did you know that more than 100,000 thunderstorms strike the United States every year, each with its own unique characteristics? Let’s delve into a basic meteorology lesson and explore a few types of thunderstorms that meteorologists often discuss. Understanding these distinctions might come in handy for trivia nights or simply impressing your friends.
1. Supercell: Known as the king of thunderstorms, supercells are accompanied by hazardous weather conditions such as large hail, damaging winds, and occasionally, tornadoes. These storms can persist for hours and cover hundreds of miles. Supercells are easily identifiable on radar, often exhibiting a hook echo that signals potential tornado activity. These storms have a distinctive appearance, resembling a “mothership” when observed in open areas. Most major tornadoes originate from supercells due to the intense wind shear in their environment.
2. Squall Line: Also referred to as a multi-cell line, this type of thunderstorm features a linear arrangement of storms that can stretch for hundreds of miles. Squall lines pose a threat of widespread damaging winds and embedded tornadoes, along with heavy rain and lightning. Bow echoes within squall lines can intensify wind gusts in localized areas. If a squall line persists for an extended period, it may escalate into a derecho, characterized by severe wind damage.
3. Pulse Thunderstorm: These storms quickly form and dissipate, earning them names like pop-up or popcorn thunderstorms. Typically occurring in summer with daytime heating, pulse thunderstorms last for less than an hour and can turn severe, producing strong wind gusts, heavy rainfall, and lightning. They form when warm, moist air rises and cools, creating cumulonimbus clouds. Due to limited wind shear, pulse thunderstorms are short-lived as the downdraft interferes with the updraft, stifling the storm’s development.
4. Multi-Cell Cluster: These clusters of thunderstorms, composed of individual cells lasting 30 to 60 minutes, are prevalent year-round but more common in warmer seasons. The outflow from each cell contributes to the overall structure of the cluster, which may persist for several hours. These clusters exhibit a mix of weather conditions and can produce prolonged periods of thunderstorm activity.
A cluster of storms can persist due to a phenomenon known as a gust front, where converging winds trigger the development of new cells. Severe weather, including hail, strong winds, and occasional tornadoes, can occur in multi-cell storms. These storms can also produce heavy rainfall, leading to flooding when additional cells form on the upwind side of the cluster and cause a “training” effect. Chris Dolce, a senior digital meteorologist with weather.com for almost 15 years, started his career with The Weather Channel in the early 2000s.
