Hurricane Lee is predicted to reach Canadian waters early Saturday morning as a post-tropical storm, likely to bring wind and rain to southern Nova Scotia and New Brunswick.
It is the third named storm to develop this year, and Bob Robichaud, a warning preparedness meteorologist with the Canadian Hurricane Centre, says the number of storms and hurricanes is already above the 30-year average.
“As of today (Sept. 12) we’re up to 14 named storms, five hurricanes and three major hurricanes,” Robichaud said. “Which is not a record, but it’s certainly up there.”
The average over the last three decades to Sept. 12 is 8.5 named storms, 3.5 hurricanes and 1.6 major hurricanes.
“We’re on pace for a busy season, which is what the updated predictions were in August,” he said.
Last month, the U.S. National Oceanic and Atmospheric Administration (NOAA) updated its predictions, saying this year is likely to be an above-normal hurricane season in the Atlantic Ocean, with a 60 per cent chance of two to five major storms, which are category three or higher hurricanes.
Hurricane season falls between June and November in Canada, but Robichaud says September and October are the peak months for the country.
HURRICANE LEE VS FIONA
Already this year Florida and Georgia were battered by Hurricane Idalia, which brought intense storm surges and flooding to much of the coast. The storm decreased in intensity and veered back into the Atlantic Ocean away from Canada.
But this week Hurricane Lee is expected to come into Canadian waters.
The country’s coast may not see hurricanes that often because warm water is needed for the storm to develop. Due to cooler water temperatures farther north, Canada is more likely to experience post-tropical storms, which can be just as intense as some hurricanes, if not more, Robichaud said.
Hurricane Lee’s predicted path toward Canada’s east coat. (Canadian Hurricane Centre)
By the time Fiona reached Canada in September 2022, it was called a post-tropical storm and unleashed heavy rain and strong winds on the Atlantic provinces.
Robichaud says cold air to the northwest, low pressure to the west and the storm adapting to cooler waters is what creates a post-tropical storm.
According to the Canadian Hurricane Centre, Lee is expected to become a post-tropical storm when it reaches Nova Scotia but likely won’t reach Fiona’s ferocity.
“Unlike Fiona, it doesn’t have those ingredients in place to re-intensify as a post-tropical storm,” Robichaud said. “So we’re looking at a pretty rapidly weakening storm as it approaches as opposed to what we saw with Fiona.”
ANXIETY IN ATLANTIC CANADA
Robichaud said many places in Nova Scotia and other provinces are still recovering from post-tropical storm Fiona.
“Fires early in the summer, floods later but we also had Fiona last year, which really caused some major damage,” Robichaud said. “And now any kind of storm that has a name on it causes some anxiety for folks here.”
Robichaud, who is based in Halifax, said the eastern part of N.S. and some parts of southwestern Newfoundland and Labrador are still rebuilding from Fiona.
“There are certainly some homes there that still have blue tarps on their roofs because of the storm from last year,” he said.
Though Lee is expected to weaken, Robichaud says its presence brings a level of stress to people and could cause damage to homes that are not protected.
Over the last several decades, about 30 to 40 per cent of the storms that form in the Atlantic make it to Canada’s “response zone.” This is the portion of ocean about 241 to 321 kilometres off the coast.
Even with the warming of the planet and higher water temperatures, Robichaud says this has held consistent for the last three decades.
HOW FORECASTERS PREDICT STORMS
Weather patterns are difficult to predict, Robichaud said, and experts use many different computer models to showcase where the storm could go and where it will hit.
Using data from ocean temperature, atmospheric conditions and past storms, experts can apply a margin of error for predictions.
On hurricane maps the cone shape around the middle of the storm showcases about a 66 per cent chance the storm will stay in that area.
“That still means that there’s a 33 per cent chance that it could at some point be outside the cone,” Robichaud said. “Every forecast, what we do is the position of a particular storm at six-hour intervals.”
A common misconception Robichaud said is that people believe the cone represents the impact of a storm, which can be “dangerous.”
“With very large storms, the impacts can extend way outside the cone, especially early in the forecast period where the cone is actually quite narrow,” he said.