Parts of Vancouver Island will see heavy rain starting Thursday as an atmospheric river approaches B.C., though it won’t be as extreme as the storm that hit the province last November, according to one meteorologist.
Derek Lee with Environment Canada says west Vancouver Island is predicted to see anywhere from 40 to 100 millimetres of rain, while eastern parts of the Island, from Victoria to Campbell River, will likely see five to 20 mm.
Calling it “rather potent,” Lee says the forecasted storm can be classified as an atmospheric river due to extreme moisture approaching from the tropics.
“Atmospheric rivers, in general, come in different shapes, sizes and intensities and durations, and this one is rather short-lived and not as intense as we saw in November 2021,” he told CHEK News in an interview.
That said, Lee finds a sudden uptick in rain can actually be beneficial depending “on how long it lasts for, what its intensity is, and where it lands to really make a dent in our systems.”
He says the coming storm will begin early in the morning and taper off by the evening before the Island experiences continuous rain into the weekend amid a fall weather pattern.
“So it isn’t until Thursday daytime that we’ll see the full potential of this system bringing a brief period of heavier rain for west Vancouver Island and more substantial rain for east Vancouver Island,” Lee said, noting that escaping the rain is unlikely, with “more showers throughout the weekend and into possibly next week.”
The typical weather pattern Islanders experience in October, November and December that’s now in full swing follows a warmer-than-usual, possibly record-breaking first half of October, according to Lee.
“I think that sharp contrast between abnormally warm temperatures to that typical fall-like weather pattern, I think everyone thinks it’s cooler. But in general, this temperature regime that we’re seeing this week is typically very normal for this time of year,” he explained.
“It’s just that for the first 15 days of the month, we were above average, even 10 degrees on some days. To say October 2022 has been in the top three warmest Octobers is not a stretch, but we still have until the end of the month to really calculate those numbers.”
Pader Brach, executive director for provincial and regional operations at Emergency Management B.C., echoes Lee, saying storms are prevalent this time of year.
“Our focus is always, each season, to be prepared for the potential for flooding, and we really want the public to be aware of that potential,” Brach told CHEK News.
He says the province is prepared to deploy four million sandbags to support local governments to protect homes and infrastructure, with gabions and tiger dams positioned to move based on weather forecasts.
“Because of the current drought that we’ve experienced in B.C., that certainly adds a level of complexity to the potential for floods and how floods can occur based on or following a significant drought,” explained Brach.
Across the province, river levels remain “particularly low,” notes Dave Campbell, head of the B.C. River Forecast Centre.
“There is going to be lots of rainfall coming in, and we do expect to see rivers recover, and we’re certainly watching out for any concerns that the rain might be enough that we might start to push into higher streamflow,” said Campbell.
Off the Island, Lee says the central coast from Bella Bella into the north coast and the Prince Rupert area will likely see the heaviest rainfall in B.C., with up to 100 mm plus 70-100 km winds.
“It’s hard to pinpoint a number, we’re still two days out,” added Lee. “As per usual, the highest likelihood of seeing precipitation will be on the outer coastline for much of B.C.”
Residents are encouraged to check Environment Canada’s website for updated forecast information.