at 5:17 PM by Mallory Schnell

Tropical Weather Terminology

Living in Kentucky, it’s easy to get much of the tropical weather terminology mixed up since we’re never directly affected. But as storms have been hitting the coasts of both Mexico and the United States within the last few weeks, it is helpful to understand the genesis of tropical weather.

According to the National Hurricane Center, a tropical disturbance is “A discrete tropical weather system of apparently organized convection — generally 100 to 300 mi in diameter…” A tropical disturbance is the weakest level of tropical cyclone development. Once the system starts to gain some organized circulation, the cyclone is considered a tropical depression. A tropical depression is upgraded to a tropical storm when it has sustained wind speeds between 39 mph and 73 mph. Last but not least, a tropical storm peaks at hurricane status once it has reached sustained wind speeds of 74 mph or more.

via Hurricane Science
via Hurricane Science

Once a storm is considered a hurricane, it is assigned a category between 1 and 5 based on its wind speed. Below is a chart of the Saffir-Simpson Hurricane Scale, which measures the strength of hurricanes:

via Rolling Harbour
via Rolling Harbour

Speaking of tropical cyclones, Tropical Storm Norbert is currently making its way up the west coast of Mexico as Post-Tropical Cyclone Dolly has dissipated. Norbert is expected to upgrade to hurricane classification.

The hurricane seasons for both the Atlantic and Eastern Pacific don’t end until November 30th, so you have plenty of time to use the knowledge you’ve learned! Be sure to visit the National Hurricane Center’s website for further general information and for updates about tropical cyclones.