VANCOUVER - The latest atmospheric river to wash over British Columbia was expected to soak parts of the south coast with as much as 150 millimetres of rain in a series of waves that won't relent until Thursday, Environment Canada said.
Rainfall warnings covered the west coast of Vancouver Island and the inner south coast, including Metro Vancouver and the Fraser Valley.
The storm's first torrent on Tuesday was to be followed by a second intense gush Wednesday and a final one early Thursday, said the weather office.
Forecasters warned warmer temperatures accompanying the storm would push freezing levels as high as 2,500 metres by Wednesday, melting mid-level snowpacks and swelling area waterways.
Emergency Management BC urged homeowners to prepare for potential floods by clearing storm drains, cleaning gutters and confirming where sandbags can be picked up from local governments.
High streamflow advisories were also posted across all of Vancouver Island and the south coast while Avalanche Canada raised the risk of a slide on Vancouver Island, south coast and Sea-to-Sky mountains to high, meaning very dangerous avalanche conditions exist.
"Wait out this storm," said a post on the Avalanche Canada website, advising that travel on southern coastal mountains was not recommended until conditions improve.
"Expect loose wet avalanches to be widespread at all elevations, and easily triggered," the site said.
Although the City of Abbotsford, which was badly damaged during catastrophic flooding in November, was covered by rain warnings linked to the storm, forecasts showed the region would likely dodge the worst of the downpours.
The latest round of storms to hit southern British Columbia reinforce the need for various levels of government to work together when it comes to flood management, says the mayor of Abbotsford.
In a statement, Public Safety Minister Mike Farnworth said the state of emergency is being extended until next Tuesday as work continues to repair damaged highways.
Abbotsford's Sumas Prairie region, a prime farming location, was devastated by November's storms and the city remains under its own a state of emergency.
Mayor Henry Braun said the city is as ready as it can be for the rain. “I just hope it won’t be worse,” he said. Braun said his largest concerns are for Clayburn Village and the Nooksack River, which runs on the U.S. side of the border.
For residents of #ClayburnVillage in #AbbotsfordBC:
— Henry Braun (@MayorHenryBraun) January 11, 2022
Prefilled sandbags are available at Albert Dyck Park and at the School House parking lot on Wright Street. First-come, first-served. More info in attached tweet. https://t.co/inwH4H3ulh
"The Nooksack needs dredging, just like the Fraser River needs dredging," he said, adding that the work has been needed since the 1970s.
Braun said the damage from November's storms combined with the latest round of weather signals the need for closer co-ordination between all levels of government for disaster and flood management.
"We've got to solve this. This has been going on for 30-plus years. We know it has to be done and if nothing else, this last year’s flooding highlights the importance of senior levels of government making long-term decisions".
Environment Canada said that part of the Fraser Valley could see no more than 10 mm of rain Tuesday, up to 40 mm overnight and a maximum of 20 mm Wednesday.
The city remains under the state of emergency, which was declared as rivers rose in November, and has told residents in low-lying areas to prepare for the potential of localized flooding.