British Columbia

Why storms on B.C.'s South Coast are hard to predict

The latest storm to hit British Columbia's South Coast may not have been as fierce as meteorologists predicted, but Environment Canada says it's not easy to forecast exactly how major weather events will play out.

Saturday's storm didn't hit as hard as some thought it would, but Environment Canada says forecasting is hard

A graphic issued by Environment Canada on Saturday shows a powerful storm hovering over southern B.C. on Oct. 15, 2016. (Environment Canada)

The latest storm to hit the South Coast may not have been as fierce as meteorologists predicted, but Environment Canada says it's not easy to forecast exactly how major weather events will play out in the region. 

Environment Canada senior climatologist David Phillips says storms can easily steer clear from major urban centres on short notice.

"If that storm chose at the last moment to veer more to the west and just brushed you, well then hey, you think it's a bust," Phillips said.

"You think the forecast was wrong, where the uncertainty was there from the get-go." 

After several days of dire warnings, many people on social media expressed disappointment, while others reminded them of the damage that was inflicted. 

But among meteorologists, Phillips says, there was never any certainty about the exact path and intensity the third storm was going to take after the two "opening acts" earlier in the week. 

"The big event being further away, the models were just a little uncertain as to the exact track it was going to take," he said.

One of the issues on the South Coast is how the ocean and the mountains may alter the path of the storm. 

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      But the other problem may simply be one of managing expectations about how much precision meteorologists can offer to begin with. 

      "There's so many elements to the storm that have to be predicted," he said.

      "It's not just, 'is it going to rain tomorrow and is it going to be a windy day or not?' That used to be the situation maybe 40, 50 years ago, But now the expectation of the public is to nail it down by the minute."

      Despite those expectations, Phillips says the reality is that it's impossible to predict exactly how a storm will play out until it's actually happening.

      Early storm season

      Phillips says something meteorologists do know for sure is that these kinds of storms usually hit later in the year — although they're not unheard of now.

      "Having three storms together in a few days, it's typically what we see often later in the season. That would be November, December," he said.

      "We've seen warmer water temperatures in the Pacific, that may have had something to do with it. It could've been a very energetic jet stream that just happened to be positioned near the coast."

      The biggest issue with storms at this time of year, he says, is that trees still have most of their leaves. This is more likely to cause harm because the branches break off easier, adding to power outages and damages. 

      He said another surprise about the trio of storms is their proximity to each other. 

      "Usually you get two or three days between them. My gosh, there were only hours between these," Phillips said.  

      With files from Kamil Karamali


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