High streamflow advisory issued for North Shore mountains, Sea-to-Sky region
Posted October 18, 2023 4:47 pm.
Last Updated October 19, 2023 4:17 pm.
As an atmospheric river cascades over B.C.’s South Coast, it has prompted a high streamflow advisory for the North Shore mountains and Sea-to-Sky region.
The BC River Forecast Centre issued the advisory for the areas Wednesday morning, which includes areas around Squamish and Whistler. They join advisories previously issued for Vancouver Island, the Sunshine Coast, and Howe Sound.
A high streamflow advisory means that river levels are rising or are expected to rise rapidly, but major flooding is not expected.
Additionally, flood watches have been issued for West Vancouver Island and the Englishman River north of Nanaimo.
The River Forecast Centre says a Pacific weather system is bringing “significant” sub-tropical moisture to the coastal regions of the province.
“On-going rises in river levels are expected throughout Wednesday and potentially overnight in areas. Minor localized flooding and road washouts are possible,” the centre said.
Dave Campbell, head of the BC River Forecast Centre, says the amount of rainfall seen in the past day is significant.
“It almost seems about a third of normal rainfall we’d see in the last six months has happened in the last day,” he told CityNews.
He advises those near rivers and other bodies of water to take caution, as water levels can change quickly.
“For people who might be out and about, we think this is going to be a real change in the rivers. We’re going to see this rapid rise and from a safety perspective, remaining cautious around rivers is important at this time,” he said.
On the drought front, Campbell says the rain will help river levels get back to normal, but things like groundwater will take longer to recover.
“We’re still trying to get a handle on the longer-term implication. I think that’s the one where it can be a little more subtle in terms of the longer-term drought things,” he explained.
The weather system has already prompted a rainfall warning to be issued for Metro Vancouver. The precipitation caused issues for drivers in the region, with many crashes reported during the Wednesday morning commute.
CityNews Meteorologist Michael Kuss says the event has brought some of the heaviest rainfall we’ve seen in a while.
“This isn’t just the heaviest precipitation we’ve had since last spring, it’s the longest sustained precipitation that we’ve had for about six months. You have to go back a while to get into a band of rain that is going to be around for almost 48 hours,” he said, adding conditions are expected to calm down by Thursday.
