What defines a "severe thunderstorm" according to the National Weather Service (NWS)?

A "severe thunderstorm" according to the National Weather Service (NWS) is characterized by specific criteria that include winds of 58 mph or greater, large hail, or the presence of a tornado. This definition is important because these conditions indicate the potential for significant damage and risk to life and property.

Winds of 58 mph or more can lead to downed trees and power lines, while large hail can cause substantial damage to cars, roofs, and crops. The presence of a tornado also escalates the severity of the thunderstorm, as tornadoes are capable of extreme destruction. Therefore, the comprehensive nature of this definition covers multiple severe weather phenomena that can occur with thunderstorms, highlighting the potential dangers they pose.

Other options do not meet the criteria as effectively. Winds of 40 mph, although potentially hazardous, are not classified as severe. Heavy rainfall exceeding 1 inch per hour, while concerning, does not inherently define a thunderstorm as severe unless accompanied by other factors listed in the correct answer. Similarly, visible lightning without rain does not indicate a severe thunderstorm, since thunderstorms can contain significant precipitation, or may even be dry storms. Thus, the correct answer encompasses the various elements that truly define a severe thunderstorm according to