Heat waves, tornadoes, and tropical storms are classed as atmospheric or meteorological natural hazards. These hazards originate from processes in the Earth's atmosphere and include extreme weather events such as storms, droughts, and heat waves. Atmospheric hazards threaten human populations and property through their potential to cause damage, destruction, and death. Specifically:

• Heat waves fall under extreme temperature hazards in the climatological category.
• Tornadoes are short-lived atmospheric events typically classified under meteorological hazards.
• Tropical storms (also known as hurricanes, cyclones, or typhoons depending on the region) are major meteorological hazards capable of causing significant damage.

In summary, these events are all types of atmospheric or meteorological natural hazards caused by processes in the atmosphere.