The Different Types of Thunderstorms

The National Weather Service defines a severe thunderstorm as a storm that is likely to produce a tornado, a hail measuring 2.5cm, and winds that travel at an average speed of 58 miles per hour. This type of thunderstorm also causes funnel clouds due to the rotation of certain columns of wind. On the other hand, vertical wind shear is the change in the speed and direction of moving air due to the increase in atmospheric height. The height and direction of this wind determine the type of thunderstorm formed. A wind shear traveling at less than 58 miles per hour forms an ordinary cell thunderstorm while one exceeding this speed becomes a severe type.

Various features make a supercell thunderstorm classified as severe. First, this type of thunderstorm produces high and large winds or long-lived tornadoes during its formation. Those winds are stronger as compared to the ordinary cell ones and thus capable of causing massive destruction to the area of formation (Rotunno et al., 2017) . Secondly, supercell thunderstorms produce torrential rainfall and large-sized hails during their formation and movement. That hail can incur significant damage to plants in areas where the thunderstorm passes and thus become severe. The first effect of a severe thunderstorm on aviation is runway contamination. Severe thunderstorms may cause hailstorms and rain on the runway and thus making aircraft braking difficult. An aircraft using such a passage may skid and thus likely cause harm to passengers or destroy the surrounding property. Secondly, a severe thunderstorm causes poor visibility and is thus likely to hinder aircraft from landing or taking off. Poor visibility can also hinder pilots from locating runways or incoming aircraft and thus a likelihood of an accident. Lastly, severe thunderstorms may cause lightning which results in electronic failure or compass deviation to the aircraft.

Reference 

Rotunno, R., Markowski, P., & Bryan, G. (2017). “Near Ground” Vertical Vorticity in Supercell Thunderstorm Models. Journal Of The Atmospheric Sciences , 74 (6), 1757-1766. https://doi.org/10.1175/jas-d-16-0288.1