Atmospheric river aims 100+ mm of flooding rains at B.C.'s South Coast

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Rain started Thursday overnight for the central and north coast, but by Friday morning, the entire coast will be engulfed in soggy conditions.

Rainfall warnings are in effect for western Vancouver Island ahead of this system’s arrival.

The rain will pick up in intensity across Vancouver Island on Friday afternoon, continuing steady through Saturday afternoon. Up to 150 mm may fall along the coast, with as much as 250 mm in the mountains.

The east side of Vancouver Island is slightly protected from the rain shadow effect, but could still expect 50-100 mm in places like Nanaimo and Campbell River. Meanwhile, Victoria is forecast to see 30-50 mm of rain, which could make for the rainiest event for the region since last February.

The Lower Mainland will see persistent rain on Friday through Sunday, with some heavier periods overnight Friday and into Saturday, especially for Squamish, and North and West Vancouver. Rainfall amounts will vary greatly, from as little as 50 mm in Delta, to upwards to 125 mm in downtown Vancouver, 100-150 mm in the Fraser Valley, including Abbotsford, and over 100-200 mm in North and West Vancouver.

Expect ponding on low-lying roads, however, and landslides could become a concern in areas like Highway 4 on Vancouver Island.