You may have seen it circulating online: a big, bold headline warning that Hurricane Irma is on track to become a “Category 6” storm.
Do not be fooled. There is no such thing.
As Irma churned west with sustained winds of 185 miles per hour on Tuesday, making it among the most powerful Atlantic hurricanes on record, some armchair meteorologists suggested that there should be. On the surface, that makes some sense: The difference between successive categories on the existing scale ranges from 14 to 26 miles per hour, and Irma’s winds were 28 miles per hour past the Category 5 threshold. In the years ahead, hurricanes are quite likely to become stronger, and the strongest ones more frequent. But Category 6 still is not going to happen.
“The scale was developed 1 to 5,” Joel Myers, the founder and president of AccuWeather, said in an interview Tuesday evening. “When you develop a scale 1 to 5, there can’t be any Category 6.”
The purpose of the categories, known as the Saffir-Simpson scale, is to quantify a hurricane’s destructive power, and the destructive power of a Category 5 hurricane — one with sustained winds of at least 157 miles per hour — is virtually total. “A high percentage of framed homes will be destroyed, with total roof failure and wall collapse,” Dennis Feltgen, a spokesman for the National Hurricane Center, wrote in an email. “Fallen trees and power poles will isolate residential areas. Power outages will last for weeks to possibly months. Most of the area will be uninhabitable for weeks or months.”
The scale classifies this level of damage as “catastrophic,” Mr. Feltgen said, and “what is left after ‘catastrophic’ damage?”
This is not to say there is no difference between a…