When does a tropical depression become a tropical storm? And when does a tropical storm become a hurricane? What's the ...

Here’s a look at the system that ranks tropical cyclones ... a range of wind speeds and storm surges for each category, and the Saffir-Simpson Hurricane Wind Scale was born.

Tropical systems are categorized by wind speed, but experts say there's much more to the story when it comes to storm impacts ...

When it reaches 39 mph sustained winds, it is labeled a tropical storm. It isn’t until sustained winds of 74 mph or greater are reached that a system will be named a hurricane. At that point, the NHC ...