Busy hurricane season on the horizon, 21 names chosen

Another busy storm season is on the horizon for Atlantic Canada, with 21 predicted storms powerful enough to have a name.

Bob Robichaud, warning preparedness meteorologist with the Canadian Hurricane Centre, said the forecast is the same as last year, which is significantly higher than the 30-year average.

The prediction this year is for anywhere from 14 to 21 storms, he said. Six to 10 of them are expected to reach hurricane status, and three to six would reach major hurricane status, which is category three, four or five. 

"Everything points toward it being a season that should be more active than the long-term average," he told Information Morning Saint John.

During the Atlantic hurricane season last year,  there were 21 named storms, including seven hurricanes, or which four were considered major, according to the National Oceanic and Atmospheric Administration in the U.S. 

Robichaud said a busy hurricane season is brought on by warmer-than-normal ocean temperatures. This year, the temperature of the Atlantic Ocean is already higher than average, and the season hasn't begun yet.

"We're starting off with warm water, and that water's just going to kind of heat up over the course of the summer," Robichaud said.

Hurricane season runs from June 1 to Nov. 30. 

Robichaud said stronger storms develop in areas where wind has the same speed from ground-level up, something described as "low wind shear."

"So very small changes in wind speed or direction as you go up in the atmosphere," he said.

Robichaud said the average number of named storms forming over the Atlantic is about 14 storms a year. That's based on numbers from 1991 to 2020.

How does a storm get a name?

The list of 21 names has already been set and it includes: Alex, Bonnie, Colin, Danielle, Earl, Fiona, Gaston, Hermine, Ian, Julia, Karl, Lisa, Martin, Nicole, Owen, Paula, Richard, Shary, Tobias, Virginie and Walter. 

Robichaud said meteorologists look to a few factors to decide if a storm should be named. First, it has to be classified as a tropical hurricane. It gets that designation if it has a centre. 

Then, if it has sustained winds of at least 63 kilometres per hour, it will get a name. 

That kind of wind is "not a hugely intense storm by Maritime standards," he said. 

If that storm intensifies and the winds reach 119 kilometres or more, it keeps its name, but is referred to as a hurricane.

Robichaud said strong hurricanes are harder to predict for New Brunswick and Atlantic Canada. 

He said it's easier to predict when they are in the tropics, but once storm reach Atlantic Canada's latitude, "they're usually in some sort of transition from one type of storm to another type of storm," he said.

"Also, almost always these storms, when they're approaching us, they're actually speeding up," he said. "So trying to predict the timing of the storm and the structure of a fast-moving storm becomes much more complex."

Wind, rainfall and storm surge are the three biggest hurricane hazards.

Robichaud said the main thing to do to prepare is to know the risk. People living along the coast have to be more aware of potential storm surge than people living farther inland, he said. 

"It all starts with knowing your risks and what you need to do to come up with a plan to mitigate those risks prior to the start of the season," he said.