While there have been no named hurricanes so far this summer, experts warn the peak of the season is yet to come.
Canadian Hurricane Centre meteorologist Bob Robichaud told CTVNews.ca in a telephone interview on Wednesday that there have been three storms named so far this season, including one in June and two in early July, but none were upgraded to hurricane status.
"We're a little bit behind the curve with respect to the number of hurricanes by this date, but we are now just entering the peak of hurricane season, which is the month of September," he said. "So we'll see what September brings."
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The U.S. National Oceanic and Atmospheric Administration earlier this August trimmed its hurricane season outlook from a 65 per cent chance of above normal activity to 60 per cent.
The weather agency is predicting 14 to 20 named storms instead of 14 to 21, with the number of expected hurricanes the same at six to 10. The agency also predicts there will be three to five major storms that reach at least 111 m.p.h. (179 km/h) instead of three to six.
A typical season will see 14 named storms, with seven becoming hurricanes and three of those being major ones. Last year saw 21 named storms, a record 30 in 2020 and 18 in 2019.
The Atlantic hurricane season runs from the beginning of June to the end of November, with about two on average forming at this point in the year, Robichaud said.
A hurricane forms as warm, moist air moves over the ocean, with the vapour rising into the atmosphere, cooling and condensing into liquid droplets. This condensation releases heat, making the air lighter. As the warm air continues to rise, moist air from the ocean takes its place and creates more wind.
Robichaud said all of the ingredients are in place for a busy hurricane season overall, but factors such as higher than average wind shears — or changes in wind speed, direction or both as altitude increases — in the Gulf of Mexico, as well as drier air from the coast of Africa, are resulting in fewer storms than expected.
"But those kinds of things, they go up and they go down in the course of a hurricane season, so those inhibited factors could disappear fairly quickly and that would open the doors for storms to develop," he said.
A few areas of "disturbed" weather in the Atlantic Ocean are being monitored and could become named storms in the coming days, he said.
AccuWeather senior meteorologist Brett Anderson told CTVNews.ca last Friday that warmer water temperatures could heighten the risk of tropical storms.
"The hurricane season is off to a very slow start with nothing going on in August but there are signs that things can really start to pick up starting next week and the week after that," he said.
The United Nations World Meteorological Organization also predicts that a phenomenon known as La Nina — where natural cooling in parts of the Pacific can lead to more Atlantic hurricanes — has strengthened in recent weeks.
Robichaud said La Nina creates an environment that produces less wind shears on average over the Atlantic.
As for the impact to Canadians, he said in a La Nina year, more storms typically develop later in the season in October and early November.
And while Atlantic Canada is susceptible to tropical storms, Robichaud said inland areas in Ontario and Quebec could be impacted, as well.
In the end, he said it is not the actual number of storms in a year but the type, location and strength of these storms that are meaningful.
"It's about the individual storms," he said. "I would caution (the public) not to necessarily let their guard down, especially as we head into September, which is the peak of hurricane season."
With files from CTV News and The Associated Press
