157 miles per hour: That’s the wind speed at which a hurricane reaches Category 5, the most dangerous classification on the Saffir-Simpson scale that the National Oceanic and Atmospheric Administration uses to describe tropical cyclones. Yet as Hurricane Irma churned toward Florida this past week, its wind speeds reached 185 miles per hour — prompting false reports that it was about to become a “Category 6” storm.
In the past, scientists have resisted efforts to expand the Saffir-Simpson scale. A Category 5 storm, according to the government’s description, already causes “catastrophic damage.” Beyond that, what else is there to know? As global climate change ushers in more intense hurricanes, Americans may just find out.