How Many Hurricanes?

Over the warm waters of the North Atlantic Ocean, a storm is brewing. Huge clouds swirl like a spinning top, growing bigger and more powerful by the minute. Winds blow faster and faster until they reach 74 miles per hour—as fast as a speeding car! A hurricane is born.

Hurricanes cause some of the most extreme weather on Earth. If they roar onto land, they can wreak havoc for hundreds of miles: They flood coastlines, knock down trees and power lines, and rip buildings apart. Knowing how many hurricanes are coming and where they will strike is crucial for people living in areas frequently hit by these massive storms.

A storm is brewing over the Atlantic Ocean’s warm waters. Huge clouds swirl like a spinning top. The winds blow faster and faster until they reach 74 miles per hour. That’s as fast as a speeding car! Once the winds hit that speed, a hurricane is born.

Hurricanes cause some of the most extreme weather on Earth. If they reach land, they can cause damage for hundreds of miles. They flood coastlines, knock down trees and power lines, and rip buildings apart. It’s important for people to know how many hurricanes are coming and where they will strike.

“People want to know what to expect,” says Phil Klotzbach, a meteorologist at Colorado State University. Every year, starting in April, he and other scientists make predictions about the coming Atlantic hurricane season, which lasts from June to November. This requires a lot of data.

First, Klotzbach looks at the number of hurricanes that form in the Atlantic Ocean each year. Historically, there have been as few as 2 and as many as 15. Then he compares the data with weather conditions, such as wind speed, water temperature, and air pressure.

“People want to know what to expect,” says Phil Klotzbach. He studies the science of weather at Colorado State University. Starting in April, he and other scientists make predictions about the coming Atlantic hurricane season. The Atlantic hurricane season lasts from June to November.

Making his prediction requires a lot of data. First, Klotzbach looks at the number of hurricanes that form in the Atlantic Ocean each year. There have been as few as 2 and as many as 15 in a single season. Then he compares the data with weather conditions, such as wind speed, water temperature, and air pressure.

“We’re looking for relationships,” he says. And sometimes weather on one side of the planet affects the other side. For example, the warm tropical climate pattern in the Pacific called El Niño causes fewer hurricanes form in the Atlantic Ocean. Its opposite, La Niña, tends to cause more hurricanes.

This year, according to the forecast he made in June, Klotzbach is expecting an average season of six hurricanes. However, there’s a chance he could be wrong. “There’s always uncertainty,” he says. But, he adds, even bad predictions have a silver lining. “We can learn a lot more by forecasting hurricanes than by just observing them—especially when our prediction is a bust!”

“We’re looking for relationships,” he says. Sometimes weather on one side of the planet affects the other side. For example, El Niño is a warm tropical climate pattern in the Pacific. During an El Niño year, fewer hurricanes form in the Atlantic Ocean. Its opposite, La Niña, usually causes more hurricanes.

Klotzbach thinks 2017 will be an average year. He expects six hurricanes. This prediction is based on the forecast he made in June. However, there’s a chance he could be wrong. “There’s always uncertainty,” he says. But even bad predictions have a silver lining. “We can learn a lot more by forecasting hurricanes than by just observing them," he says. "Especially when our prediction is a bust!”