River Forecast Centre has issued a flood watch for Vancouver Island. The heaviest rainfall is forecast over West Vancouver Island and the Coast Mountains. In these areas, total rainfall from Saturday to Wednesday is forecasted to be 200 to 300 mm, with the potential for some areas to receive up to 400 mm.
Rivers are expected to rise over the weekend and into next week. Peak river levels are expected to occur in most areas from Sunday to Tuesday and may extend from Tuesday to Thursday for lake-driven rivers, with river modelling indicating a ‘high likelihood’ of moderate flood conditions developing in areas with the heaviest rainfall and a chance that more severe flooding could occur.
Concerns on Vancouver Island include the Gold River, Salmon River, Somass/Sproat Rivers, Englishman River, Qualicum River, Chemainus River, Cowichan River and other surrounding rivers. The Flood Watch is also in effect for the South Coast, including Howe Sound, Sunshine Coast, North Shore Mountains, Fraser Valley-North, and tributaries from Port Coquitlam to Harrison Vancouver Island.
On the South Coast, flooding concerns are for tributaries around Howe Sound, including the Stawamus River, Squamish River, Mamquam River, and Cheakamus River and tributaries around the North Shore, Fraser Valley North, and the Sunshine Coast.
“Current forecasting indicates the strongest atmospheric river event making landfall on Monday, with the potential for additional rainfall in the middle of next week,” the centre notes.
Areas around Howe Sound, Sunshine Coast, Vancouver Island, Metro Vancouver, Sea-to-Sky, and Fraser Valley are expected to receive between 70 and 250 mm of precipitation. As temperatures rise, snowmelt will provide additional runoff to rivers, causing them to rise over the weekend and next week. River levels are expected to peak from Sunday to Thursday, and there is a high likelihood of moderate and even severe flooding in some areas.
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