Oct 7, 2016

How Hurricane Matthew surprised everyone and became a catastrophic storm

Jacksonville, FL
Rachel Becker
The Verge
Image: US Navy
Image: US Navy

Hurricane Matthew is roaring northward after devastating Haiti earlier this week. The Category 4 storm was the strongest hurricane to hit the impoverished island nation in more than 50 years, and the death count continues to rise. Now, it’s on its way to Florida.

The National Hurricane Center cautions that Hurricane Matthew could cause catastrophic damage if it hits Florida. "A major hurricane has not impacted this area in 118 years, since October 2nd 1898. There is NO local living memory of the potential of this event," warns the National Weather Service in Jacksonville, Florida in a briefing...

"All of our tools were suggesting a hurricane, but not a strong hurricane," says Chris Landsea, the science and operations officer for the National Hurricane Center. And Matthew started out small. But over 24 hours, it grew in strength. "We had no clue that it was going to become Category 5, or a Category 4." Both categories mean catastrophic damage that leaves some regions uninhabitable (the wind speeds of a Category 5 storm reach more than 157 miles per hour)...

Matthew was a Category 4 when it hit Haiti. Winds at speeds up to 145 miles per hour tore through the country and torrential rains pummeled it...At least 100 people have died...

Deep, warm pockets of water fuel hurricanes. So when they pass over cooler spots, or especially land, they usually lose speed. That’s especially true for mountainous regions, says Kristen Corbosiero, a hurricane researcher at State University of New York in Albany. Mountains slow the low, fast, swirling winds with friction as well as by interfering with their circulation.

But even after it traveled across the mountains of Haiti and Cuba, Matthew’s speed only dipped to a Category 3 — which means wind speeds of up to 129 miles per hour. That’s enough to uproot and snap trees. Such a storm can still create flash floods, mudslides, and storm surges which The National Hurricane Center warns are life-threatening.

Now, as the hurricane’s eye sets its sights on the city of Freeport in the Bahamas, winds are reaching 140 miles per hour. The eastern coast of Florida is next, and the National Hurricane Service has extended its hurricane warning as far north as South Carolina.

Florida might not prove much of an impediment to the hurricane’s speed: the state is basically sea level, it’s warm, and it’s humid, Those are hurricane-friendly conditions, and are unlikely to slow it much.

"From a scientific perspective, when you look at this, you say ‘Wow, Mother Nature has really created this masterpiece,’" Shay says. "But on the other hand, for John and Jane Q Public, this is a disaster"