Worst of atmospheric yet to come

B.C.’s River Forecast Centre said Sunday morning the worst is yet to come in a series of atmospheric rivers drenching the province’s South Coast.

The centre says the strongest system is expected to arrive Monday and persist throughout the region until the middle of the week.

It says the heaviest rainfall will hit western Vancouver Island and the Coast Mountains, with between 200 and 400 millimetres in the forecast.

The river centre has issued flood watches covering all of Vancouver Island and much of the South Coast, while a rainfall warning from Environment Canada spans parts of Metro Vancouver and Howe Sound.

Environment Canada issued a special weather statement for Metro Vancouver and surrounding areas Saturday morning, saying incoming storms will increase the potential for flooding, water pooling on roads, power outages, and possible landslides.

The statement applies to Metro Vancouver, the Sunshine Coast, and parts of Vancouver Island.

Environment Canada meteorologist Armel Castellan says residents should expect “long duration” rainfall events Saturday and Sunday.

Castellan says although it won’t be as bad as the recording-breaking 2021 floods that washed away bridges and prompted landslides that killed five people, people still need to stay away from fast-moving rivers this time.

The weather service says it isn’t sure where the worst of the storm will be felt or exactly when the heaviest rains will fall.

“The heaviest rainfall is expected to occur between Sunday night and Monday,” the statement says. “There will be periods of lighter rain between the storms, but it is the cumulative effects of the storms that is likely to be impactful.”

The storms are bringing warmer temperatures, and mountain snow melt is contributing to the flood risks. The weather service says vulnerable areas such as burn scars are particularly vulnerable to landslides due to heavy rain falling on surfaces that are already saturated.

Strong winds will mean an increased risk for power outages due to the potential of falling tree branches.

Meanwhile, a flood watch issued by B.C.’s River Forecast Centre Thursday remains in place as rain pounds the South Coast Saturday.

The watch applies to the Sunshine Coast, Sea-to-Sky, North Shore mountains, Fraser Valley, and Vancouver Island.