'Tropical new year' in cards as record-breaking warm spell hits Ottawa

Snow melts in downtown Ottawa on the second-consecutive day of record-setting warmth. (David Bates/Radio-Canada - image credit)
Snow melts in downtown Ottawa on the second-consecutive day of record-setting warmth. (David Bates/Radio-Canada - image credit)

A spell of unseasonably warm weather has seen Ottawa break longstanding temperature records for two straight days.

Friday saw temperatures hit 9 C in Ottawa, shattering the previous Dec. 30 high of 6 C recorded at the city's airport in 1990.

Another record fell Thursday afternoon, as the mercury reached 6.9 C. The previous 6.2 C record for Dec. 29 had stood since 1982.

"It really is quite spectacular ... not only how warm it's going to be, but the duration of this kind of winter heat wave," said David Phillips, senior climatologist with Environment and Climate Change Canada.

Phillips said Ottawa will see as many days with above-zero temperatures through the end of December and into early January as it had days below freezing prior to the warming period.

"[It's] a polar Christmas and a tropical new year," he said. "The look and the feel of winter is disappearing quickly from the Ottawa area."

David Bates/Radio-Canada
David Bates/Radio-Canada

Rainfall warning issued Friday

That makes flooding in the region a concern, Phillips added, as potentially record-breaking rain may combine with warm temperatures to melt the heavy snow pack.

Environment and Climate Change Canada issued a rainfall warning for Ottawa Friday afternoon, warning that 20 to 30 millimetres could fall by Saturday night.

The fact the ground is still frozen makes it harder for that rain to be absorbed, the agency said.

The City of Ottawa said in an email to CBC Thursday that it was already "proactively opening up catch basins" in an effort to give rain and melted snow a place to drain.

"In the coming days, crews will be monitoring areas at risk of localized flooding during winter rainfall events and will be ready to respond to immediate flooding concerns," said Quentin Levesque, the city's director of roads and parking services.

Concerns for Winterlude, Skateway

Gerald Cheng, a meteorologist for Environment and Climate Change Canada, said the high temperatures are due to a warm air mass coming from the Gulf of Mexico.

Cheng said while he expects temperatures to gradually drop, they should still remain higher than normal through much of January.

Phillips said that could pose problems for Winterlude and the Rideau Canal Skateway.

"We clearly see that as a concern, I think, from the tourism and recreation aspects of the Ottawa area," he said.

Environment Canada has been recording temperatures at the Ottawa airport since 1938.

But temperature data stretching back to 1873 also exists for the city. Prior to 1938, Environment Canada measured temperatures at a site near the Central Experimental Farm, rather than the airport.

Based on those numbers, Thursday's heat broke a record that had stood since 1889, while Friday broke the previous record of 8.3 C, set in 1936.