How Hurricanes Get Categorized

As Hurricane Florence heads toward the East Coast, meteorologists say that the storm, which is listed currently as a Category 4, could strengthen to become a Category 5. There is nothing higher than a Category 5, which means storm winds could be fast enough to cause extreme, catastrophic damage. However, if the hurricane does reach that level, it does not mean it will stay there. The New York Times writes that the storm’s strength may fluctuate as it travels, and hurricanes tend to weaken as they pass over land.

Florence is expected to make landfall Thursday night. Experts say that the storm surges could be life-threatening and heavy rains could cause flooding inland. Some areas could lose power for days.

LATEST: Category 4 Hurricane Florence is now about 530 miles from the North Carolina coast, NHC says. https://t.co/Wa7cSPtIy9

• Maximum sustained winds are near 130 mph
• Hurricane and storm surge warnings issued for parts of NC/SC coast https://t.co/toYURjJcu8

— NBC News (@NBCNews) September 12, 2018

But what makes a hurricane Category 4 or 5? The scale was created in 1969 by Herbert Saffir, a structural engineer, and was expanded with the help of Robert Simpson, former director of the National Hurricane Center. The five hurricane categories are based on wind speeds and are mostly meant to help predict structural damage.

“It’s not just meteorological,” said Joel Cline, a hurricane support meteorologist with the National Oceanic and Atmospheric Administration, to The Times. “It’s more of an impact-based scale.”