‘Catastrophic’ Laura is now a Category 4 hurricane. Here’s what that means

Mark Price
·3 min read

Hurricane Laura became a Category 4 storm Wednesday afternoon, and the National Hurricane Center is using words like “devastating” to describe the potential impact along the Gulf Coast.

What does Category 4 mean?

For starters, the Saffir-Simpson Hurricane Wind Scale only goes to Category 5. (Hurricane Katrina was a Category 5, with winds of 175 mph.) Laura’s winds were 145 mph Wednesday evening and picking up speed, according to the hurricane center.

When a storm reaches Category 4, its winds are 130 mph to 156 mph, a shift that bumps the potential damage from “devastating” to “catastrophic,” the NHC says.

“Well-built framed homes can sustain severe damage with loss of most of the roof structure and/or some exterior walls,” according to Saffir-Simpson scale.

“Most trees will be snapped or uprooted and power poles downed. Fallen trees and power poles will isolate residential areas. Power outages will last weeks to possibly months. Most of the area will be uninhabitable for weeks or months.”

Then there’s the rain: Up to 15 inches is now forecast at the site of Laura’s expected landfall along the Texas-Louisiana border, and 4 to 10 inches will fall as far north as central Arkansas, forecasters say. Widespread flooding — including roads in urban areas — is likely from far eastern Texas, across Louisiana and into Arkansas, the NHC said Wednesday.

“A few tornadoes are expected this afternoon (Wednesday) through tonight over Louisiana, far southeast Texas, and southwestern Mississippi. The risk for a few tornadoes should continue into Thursday across Louisiana, Arkansas, and western Mississippi,” the center said.

An impact area that broad is one of many indications of how “large” Laura is becoming, experts say.

Hurricane-force winds (over 75 mph) were extending 60 miles from the center Wednesday evening, while tropical-storm-force winds (up to 74 mph) were being felt 205 miles out, according to the National Hurricane Center.

A wind gust of 107 mph was recorded Wednesday by a buoy just east of the storm’s eye, along with a wave that measured 37 feet high, the center reports.