(Bloomberg) -- Hurricane Fiona is on track to rake Bermuda with damaging winds before driving north toward Atlantic Canada, bringing threats of widespread damage and power outages in its path.
Fiona, the strongest storm so far in this year’s Atlantic hurricane season, is about 410 miles (660 kilometers) southwest of Bermuda and is set to deliver its worst to the islands later Thursday, the US National Hurricane Center said in its 11 a.m. advisory. Top winds are at 130 miles per hour, where they have been for the past day.
Fiona will likely come ashore in Atlantic Canada with winds of 90 mph, a Category 1 storm on the five-step Saffir-Simpson scale, the US center said. Upwards of 10 inches (25 centimeters) of rain could fall in isolated areas across the Maritime provinces of Nova Scotia and Prince Edward Island.
Hurricane watches have been posted across parts of Nova Scotia, PEI and western Newfoundland, according to the Canadian Hurricane Centre.
“The storm is shaping up to be a severe event for Atlantic Canada and eastern Quebec,” the Canadian agency said in a statement. “Severe winds and rainfall will have major impacts for eastern Prince Edward Island, eastern Nova Scotia, western Newfoundland, eastern Quebec and southeastern Labrador.”
Before its Canadian landfall, the hurricane could shake Bermuda with 90-mph winds overnight, causing some damage and power outages, said Chuck Watson, a disaster modeler for Enki Research. The lower wind speeds on Bermuda are because the storm won’t make a direct strike, but rather its edge will hit the islands.
Fiona could end up causing more than $10 billion in damages and losses, with the worst in Puerto Rico and the Dominican Republic. A slight shift of its track could bring $1 billion or more in damages across Atlantic Canada, he said.
Bermuda’s strong building code could limit damage, but in Canada the strong winds raise the risk of leafy trees toppling and knocking down power lines, causing outages, according to Adam Douty, a meteorologist with AccuWeather Inc. Leaves add extra stress to trees and their branches during high winds.
‘Unusual’ Storm
Fiona could end up being the strongest September storm to hit Canada based on central pressure, another way to measure strength, said Jeff Masters, a meteorologist for Yale Climate Connections and co-founder of Weather Underground. The central pressure could reach as low as 950 millibars. The all-time lowest central pressure measured in a Canadian storm of any kind was 940 millibars.
“Fiona will be a record-breaking storm for Canada, but its main impacts will be to a low-population area, and I doubt it will approach Canada’s most expensive hurricane of all time, Juan of 2003, in terms of damage,” Masters said. “It is certainly going to be really unusual for this time of year.”
As Fiona pushes north it will transition from a true tropical system to a post-tropical cyclone, changing its structure. Fiona’s strongest winds may not be at its center, for example, and it will draw power from pressure and temperature gradients in the atmosphere and not from warm ocean water.
Fiona is one of two storms in the Atlantic. Tropical Storm Gaston is meandering near the Azores, where it currently isn’t a threat. Forecasters are also watching a swirl of thunderstorms and showers moving through the Caribbean that carry a 90% chance of becoming a new system by next week. That system could threaten the eastern Gulf of Mexico, and Masters said it has the potential to cause damage through the region.
(Updates with Canadian watches starting in third paragraph.)
©2022 Bloomberg L.P.
Advertisement