Canadian Hurricane Centre predicts below average hurricane season

Meteorologists work at the Canadian Hurricane Centre, tracking Hurricane Gonzalo, in Dartmouth, N.S. on Friday, October 17, 2014. (Andrew Vaughan / THE CANADIAN PRESS)

HALIFAX -- This year's hurricane season will likely be quieter than average due to the so-called El Nino effect and cooler ocean temperatures, but the Canadian Hurricane Centre warned Wednesday that Canadians shouldn't let their guard down.

Meteorologist Bob Robichaud said even quieter hurricane seasons, which run from June to November, can generate potentially damaging and deadly storms.

Robichaud pointed to last season, which was also below average at eight named storms. Yet post-tropical storm Arthur, the first storm to blow through the region, caused damage across eastern Canada and knocked out power for hundreds of thousands of people in early July.

"It only takes one storm to make it a bad year," said Robichaud at a news conference in Halifax. "Even though there's a low number of storms in the entire Atlantic basin, you can still get a very damaging storm on any given year."

Robichaud said El Nino, a patch of warm water in the Pacific Ocean, can interfere with the formation of hurricanes in the Atlantic by increasing wind shear, or the change in wind speed and direction.

"If the winds are in different directions at different speeds at different altitudes, the storm actually gets sheared apart before it really gets going," said Robichaud.

Robichaud said hurricanes draw heat from the ocean and pump it into the atmosphere, so when the water is cooler, there are fewer storms.

In the United States, the National Hurricane Centre is predicting six to 11 named storms this season, slightly below the average of 12 named storms.

It says three to six of those will develop into hurricanes, with top sustained winds of at least 74 mph. Up to two will be major storms of Category 3 or higher, with winds of at least 111 mph.

This season has already seen its first storm, post-tropical storm Ana, which came ashore in North Carolina earlier this month, bringing rain from Virginia to South Carolina. It did not cause any major damage.

Last year's hurricane season produced eight named storms, four of which made it into the Canadian response zone off Atlantic Canada.

Robichaud said roughly two or three storms travel through the zone yearly, with one or two having some sort of impact on Canadian land mass.