Canada's Top Ten Weather Stories for 2012
2. Super Storm Sandy and Another Active Hurricane Season
Forecasters were right on the money when they accurately predicted another active Atlantic hurricane season in 2012. At season’s end, there were 19 named storms from Alberto to Tony, 10 of which became full-blown hurricanes, but only Michael logged in as major storm with winds above 178 km/h. The busy storm season reflected a continuation of above-normal activity that began in 1995. Since then, all but two years have been at or above normal. The season began quickly with two tropical storms hitting a week before the official June 1 launch. In August, eight tropical cyclones reached storm intensity breaking the previous record of seven in August 1933 and 1995.
Chris was the Atlantic’s first hurricane of the season. In Canadian waters, the storm brought high waves and swells to Newfoundland’s Grand Banks on June 22 but negligible rains and winds to the Avalon Peninsula. On September 4, a well-defined low pressure system (including the remnants of Hurricane Isaac) made a slow passage across the lower Great Lakes and St. Lawrence River. A general rainfall of about 40 mm fell adjacent to the north shore of Lake Ontario and 50 to 70 mm in southern-most Quebec. Locally, higher amounts in Ontario occurred in Markham (87 mm), Richmond Hill (104 mm) and Point Petre (98 mm), and in Quebec at Frelighsburg (100 mm). Heavy rain in these locations set all-time September records and led to localized flooding.
Hurricane Leslie was a large storm more than 800 km in diameter packing loads of rain and powerful winds that hit Newfoundland and Labrador on September 11. Adding to the mess was a trough of low pressure that tapped Leslie’s moisture and created problems across the Maritimes. The system stalled over western Prince Edward Island, dumping copious amounts of rain in advance of Leslie’s arrival. At Charlottetown, a two-day total of 128 mm of rain was more than the total rainfall in the city in July and August combined. And in Nova Scotia, heavy rains of 100 to 150 mm soaked parts of the province leading to extensive tide-enhancing flooding and forcing evacuations of 50 families along the Salmon and North rivers near Truro when two dykes were breached. The only ones welcoming the rain were apple growers in moisture-starved Annapolis Valley. The remains of Hurricane Leslie made landfall in Fortune, Newfoundland and Labrador at approximately 8:30 a.m. on September 11, barrelling along at speeds up to 65 km/h before exiting out to sea north of Gander. Had the storm arrived a few hours earlier at high tide, conditions would have been worse. Before departing, the storm pummelled the Island with several hours of stiff winds and heavy rains. Bad weather and eight-metre waves forced Marine Atlantic to cancel crossings between Nova Scotia and Newfoundland. Higher waves at 15 m occurred along the southern Avalon. Winds east of the storm’s centre were fierce gusting up to 131 km/h, tearing apart roofs, stripping off siding and cladding, toppling trees and fences, overturning trucks and snapping power lines. Parks in St. John’s were a mess of fallen branches and uprooted trees. At the height of the storm, approximately 100,000 customers on the Avalon Peninsula lost power. Meanwhile, in western Newfoundland, the challenge was excessive pounding rain with Cow Head recording 108 mm of rainfall. The next month, on October 18, post-tropical storm Rafael blew more than 500 km offshore Newfoundland and Labrador but was close enough to whip up wild seas that crashed through a breakwater in Trepassey on the southeastern coast.
A few days later, on October 20, Hurricane Sandy was born in the southwest Caribbean Sea from a cluster of powerful thunderstorms. As it churned north and northeastward, ominous warnings started that Sandy would do an abrupt and improbable left turn aimed directly at the Jersey Shore and New York City. A massive cold front that was stalled over the lower Great Lakes eagerly drew in Sandy’s moisture and momentum completing her transformation into a mid-latitude storm. Late on October 29, Storm Sandy morphed into an intense post-tropical system no less potent than it had been hours before. The once super-sized hurricane with tropical-force winds that at one point extended across 1,000 km over the open ocean now became even bigger and broader as a hybrid storm with warnings extending over half a continent from Chicago to Halifax and Georgia to Timmins.
In Canada, Sandy could be better characterized as a nasty fall storm. Sustained winds of 70 to 80 km/h were reported throughout southern Ontario and Quebec. At its worst, Sandy’s wind gusts topped 106 km/h on Western Island in Georgian Bay, 100 km/h in Sarnia, 95 km/h near Burlington and 91 km/h at Toronto Island. In Quebec, gusts reached 87 km/h in Laval and 91 km/h at Île d’Orléans. Strong winds also whipped up the Great Lakes, generating waves of up to seven metres at the south end of Lake Huron. Storm surge warnings were issued in the Gaspé and along the north shore of the St. Lawrence River. The storm generated six-metre waves near the West Scotian Slope and Grand Manan Island, and gale-force winds of 70 km/h in the Bay of Fundy. Rainfall totals ranged between 20 and 40 mm across southern Ontario, and in Charlevoix, Quebec totalled 185 mm over 73 hours. Two rivers spilled their banks causing local damage to some municipal infrastructures. Over parts of northeastern Ontario and western Quebec, rain turned to snow, mixed with ice pellets and patchy freezing rain driven by gusts of up to 60 km/h. Out of nowhere, Sandy even spawned a weak tornado in Mont Laurier, Quebec on October 31. Twisting winds destroyed an old barn and knocked over road signs. In Ontario, the storm was implicated in two deaths and forced the cancellation of train and air travel. And when all was said and done, upwards of 150,000 customers in Ontario, 50,000 in Quebec and 14,000 in Nova Scotia were left without power. According to Property Claim Services Canada insurance losses from Sandy in Canada exceeded $100 million.
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