ELK VALLEY, BRITISH COLUMBIA — High streamflow advisories have been issued for two more regions as heavy rain sweeps over British Columbia's southern Interior.
B.C.'s River Forecast Centre added the advisories for the Similkameen and Okanagan regions after previously issuing bulletins for all of Vancouver Island, the Sunshine Coast and Metro Vancouver through to the Fraser Valley.
Advisories are also in place for the Boundary and Kootenay regions where up to 50 millimetres of rainfall is expected before showers ease on Tuesday.
The centre issues high streamflow advisories when water levels could rise rapidly and minor flooding in low lying areas is possible, but no major flooding is expected.
It says up to 200 millimetres of precipitation is expected over parts of B.C.'s south coast, with high flows projected in rivers throughout the North Shore mountains, Howe Sound, the Lower Mainland, the Fraser Valley and Vancouver Island.
In the southern Interior, the river forecaster says flows are below normal as the spring freshet has yet to set in, but the rainfall is expected to cause rapid increases in water levels, with smaller, low-elevation creeks and rivers at greatest risk.
"These rain-on-snow events have a high amount of uncertainty based on rainfall totals, ripeness of the snowpack to melt and the fluctuation of the freezing level," the centre said in a bulletin updated Monday afternoon.
The rain follows a Pacific frontal system that Environment Canada said washed over Vancouver Island and the south coast over the weekend, bringing up to 90 millimetres to Haida Gwaii and more than 80 millimetres on Saturna Island.
This report by The Canadian Press was first published April 10, 2023.
The Canadian Press
