High winds blew in, then blew right out

By Jeremy Appel on October 19, 2017.

jappel@medicinehatnews.com @MHNJeremyAppel

Tuesday night’s wind storm swept through southern Alberta, reaching a peak speed of 102 kilometres per hour in Medicine Hat, then quickly dissipated.

“What surprised a lot of our forecasters was the … travelling speed,” said David Phillips, a senior climatologist with Environment Canada. “It was almost like it hit and ran.

“Not often do these wind storms die down as quickly as this one came. It really just hightailed it out of town.”

He called the storm a “big blow,” which originated in the Gulf of Alaska.

“We saw a number of weather systems already and later this week barelling in from that area,” said Phillips. “There’s almost a parade of them.”

It took only five hours for the storm to move from British Columbia and Alberta to Manitoba, which he said is highly unusual.

“That’s a really fast-moving weather system,” Phillips noted.

The peak wind reached Medicine Hat around 6 or 7 p.m., the result of a brief gust, rather than a sustained wind, he added.

“These gusts can cause stress on buildings, damage on trees (and) power outages,” Phillips said. “It’s not the sustained wind that necessarily creates the problems. It’s often the gusts.”

The storm caused some grassfires, which Phillips said is somewhat atypical.

“It was almost ironic,” he said. “I looked at the weather warnings this morning and I saw both wind and smoke from grassfires.

“You normally don’t see that. Sometimes the strong winds just blow the smoke away. The fact that the wind was short lived (meant) it helped to fan a few flames.”

By 8 p.m., the sustained wind was about 84 km/h, considerably less than the gust’s top speed of 102.

“It was pretty well over by midnight,” Phillips said.

He said southern Alberta is typically windier than the rest of the nation, particularly during the autumn months, although April and May tend to be the windiest overall.

“October is a windy time,” said Phillips. “Often what happens in that month is you get a change of season — summer to winter — and that’s what happens when you get that transition season.

“Getting strong winds at this time of the year is not rare. It’s just part of your normal climatology.”

Out of Environment Canada’s windiness rankings for the entire year in 91 locations throughout Canada, the Hat ranks 48th. By contrast, Lethbridge ranks fifth.

A wind storm identical to Tuesday’s occurred in southern Alberta on June 12, 2015.

“It was exactly the same,” he said, adding that its peak speed was also102 km/h. “It was rip-roaring kind of day.”

22
-21