What constitutes a Category 5? – NBC New York

First Helene, now Milton. Two major hurricanes have devastated — or in Milton's case, will devastate — parts of Florida in the last week and a half, leaving many trying to understand the extent of the weather systems.

The National Hurricane Center uses the Saffir-Simpson Hurricane Wind Scale to determine storm categories. It's a rating of 1 to 5 that's based only on a hurricane's maximum sustained wind speed and doesn't take into account other potentially deadly threats like storm surge, rainfall, flooding and tornadoes — the first three of which occurred in droves with Hurricane Helene. Possible property damage is also estimated, ranging from “some damage” to “catastrophic.”

Here are the wind thresholds for the different hurricane categories and the type of damage they can cause, according to the NHC.

Breakdown of hurricane categories

Category 1 (maximum sustained winds of 74-95 mph): Very dangerous winds may cause some damage. Well-built frame homes can have damage to the roof, shingles, vinyl siding, and gutters. Large tree branches break and shallow-rooted trees can fall. Extensive damage to power lines and poles will likely result in power outages lasting a few to several days.

Category 2 (maximum sustained winds of 96-110 mph): Extremely dangerous winds will cause major damage. In well-built half-timbered houses, significant roof and facade damage can occur. Many shallow-rooted trees are snapped or uprooted and block numerous roads. An almost complete power outage is expected, with outages lasting several days to weeks.

Category 3 (maximum sustained wind speeds of 111-129 mph): Devastating damage will occur. Well-built half-timbered houses can experience significant damage or removal of roof coverings and gable ends. Many trees are snapped or uprooted, blocking numerous roads. Electricity and water will be unavailable for several days to weeks following the storm.

Category 4 (maximum sustained winds of 130-156 mph): Catastrophic damage will occur. Well-built frame houses can suffer serious damage due to the loss of most of the roof structure and/or some exterior walls. Most trees are snapped or uprooted and power poles are toppled. Fallen trees and utility poles will isolate residential areas. Power outages can last weeks to possibly months. Most of the area will be uninhabitable for weeks or months.

Category 5 (maximum sustained wind speed of 157 mph or greater): Catastrophic damage will occur. A high percentage of half-timbered houses are destroyed, the roof fails completely and the walls collapse. Fallen trees and utility poles will isolate residential areas. Power outages last weeks to possibly months. Most of the area will be uninhabitable for weeks or months.