While B.C.'s coast is experiencing a “lull” in rainfall Wednesday, the third atmospheric river event to hit the province in the past week is not over yet.
During Wednesday's press conference, Minister of Public Safety Mike Farnworth said this week's rainfall is not over, and “a significant par of the storm is still to come throughout the rest of the day.” Minister of Transportation Rob Fleming said crews remain on standby on a number of B.C. highways in anticipation of more severe weather, and temporary Tiger Dams remains in place across the Trans-Canada Highway between Abbotsford and Chilliwack.
Meteorologist Armel Castellan said another 40-50 mm of rain is expected to fall across the coast and into the Fraser Valley, and warm temperatures from the atmospheric river are bringing the rains to higher elevations in the Coquihalla, Boston Bar and more interior areas.
Snowmelt from rain at higher elevation is expected to exacerbate the rainfall issues in impacted rivers. Dave Campbell of the River Forecast Centre said an additional 50-60 mm of snow-water equivalent is expected to be melted from coastal mountains, in addition to the rains.
“We are anticipating fairly challenging river conditions through the eastern side of the Fraser Valley, the Chilliwack River as well as rivers draining off both the north and south side of the Fraser Valley,” Campbell said.
“We've also seen spillover rainfall going into Interior watersheds and expecting ongoing challenging river conditions into the Tulameen River down into Princeton as well as the Coldwater River into Merritt.”
Highway 99 north of Pemberton was pre-emptively closed Tuesday based on the advice of geotechnical engineers, due to the heavy saturation of the ground through the pass. Fleming said they hope to have the highway reopened by Wednesday afternoon, depending on the weather.
Following a landslide closure along Highway 7 west of Hope Tuesday, the highway is now reopened. Fleming noted the importance of the route, which has connected commercial traffic through to Highway 3, and to the Interior of the province.
Since reopening, more than 5,000 commercial trucks have passed through the highway, while about 1,200 commercial trucks have made their way through to the Interior through northern Washington.
Trains are now also delivering goods from B.C.'s coast to the rest of the country after temporary repairs were made to tracks through the Fraser Canyon.
Castellan said a number of weather records have been broken in recent weeks on B.C.'s coast, including single-day rain records in Abbotsford and seasonal rain records in Nanaimo, Victoria, Vancouver airport and Abbotsford. Temperature records were also broken across the Okanagan Wednesday.
“This has been a very active [wet] streak since mid-September on the heels of an extremely dry and hot summer. So we have gone from some extremes to other extremes, and unfortunately this is consistent with what climate change has been projecting for all parts of Canada,” Castellan said.
“The frequency, the amplitude of these events, and their longevity individually will continue to increase with the coming years and decades.”