Friday, September 23, 2022

Severe weather warning: Hurricane Fiona will be 'historic', 'extreme weather event' for Atlantic Canada

As Hurricane Fiona heads north to Atlantic Canada, experts are anticipating it to be a historic, record-breaking storm in Canada.

"Where it fits in the history books, we'll have to make that determination after the fact, but it is going to be certainly a historic, extreme event for eastern Canada," Bob Robichaud, warning preparedness meteorologist with Environment Canada told reporters on Friday.

"It's very powerful at the present time, it's still a major hurricane and it's only 900 kilometres away from us, and it's getting bigger. So all that momentum is trapped within the storm, it's very difficult for something like that to actually wind down as it's approaching."

Robichaud added that the storm size is bigger than Hurricane Juan from 2003 and comparable in size to 2019's Hurricane Dorian, but Fiona is stronger.

On Thursday afternoon, the warning preparedness meteorologist said this is "going to be a storm that everyone remembers."

Brett Anderson, senior meteorologist with AccuWeather, says this looks like it's probably going to be the strongest storm, in terms of low central pressure, on record for Canada.

"Almost every computer model is telling us it's going to be at least 935 millibars or lower, even down into the 920s," Anderson told Yahoo Canada. "So most likely, this is going to be end up being the strongest storm in Canada's history, in terms of the central pressure."

The current record is 940 millibars, which Newfoundland saw in 1977.

"It's already strong, and...the ocean water between Bermuda and Atlantic Canada is abnormally warm, it's anywhere from two to four degrees Celsius above normal," Anderson said. "So the water is warmer and allows more energy for the storm to maintain itself."

"Another ingredient for why this is going to remain very strong, we have a strong piece of energy, basically a cold front, which brought on cold air into Eastern Canada yesterday and today,...but that front is also going to merge with the hurricane, and actually add some energy to the hurricane, it's going to re-energize the hurricane a little bit."

Hurricane Fiona becomes a dangerous category 4 storm over the Atlantic south of Bermuda. This colorful infrared satellite image belies the power and strength of this tropical storm. The brighter tops show higher clouds with the black in the northwest quadrant being the coldest / highest. A well developed eye has formed with banded upper outflow depicted in this satellite imagery.

When will the storm hit Atlantic Canada?

AccuWeather has identified that the centre of the storm will make landfall over extreme eastern Nova Scotia around 5:00 a.m. ADT on Saturday.

"That's what it looks like and confidence is pretty high with that," Brett Anderson said.

He added that the expected worst conditions will be seen in Nova Scotia and Prince Edward Island early Saturday morning, possibly into early afternoon. Later Saturday afternoon and Saturday night, the storm will "begin to steadily weaken," the winds will start to come down and the rain will being to ease up as well.

"Even as the storm pulls away on that south side of the storm, it's still going to be windy right into late Saturday," Bob Robichaud said on Friday.

"So the impact of having winds that strong for that long, it just creates more stress on everything like the trees, like structures. So that's why we're particularly concerned about wind."

The Environment Canada forecast expects Hurricane Fiona to move north across Nova Scotia on Friday night, passing through Cape Breton Saturday morning, and reaching the Quebec Lower North Shore and Southeastern Labrador early Sunday. Environment Canada indicates that "severe winds and rainfall" are expected to have "major impacts" for eastern Prince Edward Island, eastern Nova Scotia, southern and eastern New Brunswick, western Newfoundland, eastern Quebec, and southeastern Labrador.

The warning from Environment Canada on Friday morning also states that, "most regions will experience hurricane force winds." There is also a "high likelihood" of storm surge for parts of Nova Scotia, the Gulf of St. Lawrence and western Newfoundland.

"The southwestern part of the Gulf of St. Lawrence, in those north to northwesterly winds, that's where the water is going to be pushed on shore and it's going to be close enough to the centre of the storm where pressure is going to also contribute to that storm surge," Robichaud said. "Right now, our modelling suggests that storm surge, depending on the area, could be anywhere from about 1.8 to 2.4 metres, so significant rises in water level because of that surge."

"It also suggests that maybe in some areas, the peak surge may not be totally timed with the high tide However, any kind of delay in the storm in arriving will result in that peak surge actually arriving a little bit later, which could coincide with time with high tide... So tomorrow morning is when we're we have the highest concern for potential coastal flooding."

The Environment Canada forecast guidance suggests that 100 to 200 mm of rainfall will be present, but closer to the path of Fiona, more than 200 mm is "likely," but those estimates do include the rainfall from Thursday night and Friday.

Anderson warned that this amount of rain will cause flooding and with winds anywhere from 160 to 190 kilometres per hour, particularly in Prince Edward Island and eastern Nova Scotia, there is going to be tree damage, and likely several power outages.

"We could be dealing with...widespread power outages across Prince Edward Island, western Nova Scotia, southwestern Newfoundland, that could last days, if not weeks," Anderson said.

"Stay home, do not travel is absolutely necessary... Be prepared for power outages, so preparations should be made by this evening in terms of making sure your generator is ready, making sure you have restocked enough with food, nonperishable food."

While the storm will hit the Nova Scotia coast first, the impacts in Quebec are expected to worsen in the Magdalen Islands by Friday evening with rainfall expected to be in the range of 15 to 25 mm per hour, with strong winds until late Saturday, expected to last about 12 hours. The expectation is that there will be extensive power outages, particularly near the coast, and between 75 and 125 mm or rain in the Magdalen Islands, with about 30 to 50 mm of rain in the Gaspé Peninsula, and in the lower north shore, a little more than 50 mm of rain in some areas.

Environment Canada is stressing that residents in the path of the storm need to stay up-to-date on the forecast and learn how to prepare at getprepared.ca.

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