Thunderstorm watch in effect for B.C. Interior; landslide warning issued

CBC News

· Posted: Jun 22, 2025 7:49 PM EDT | Last Updated: 21 minutes ago

A terrible thunderstorm ticker crossed B.C.'s confederate Interior has prompted the Lower Similkameen Indian Band (LSIB) to widen a landslide informing successful parts of the Similkameen Valley already susceptible owed to past wildfires.

Environment Canada issued a thunderstorm ticker connected Sunday for the Okanagan, Shuswap and West Kootenay regions, including Kelowna, informing of imaginable hail, flash flooding and beardown upwind gusts. 

In response, the LSIB has extended its slope monitoring strategy informing for the Ashnola and Chopaka areas until 1 a.m. PT connected June 26. The archetypal alert was acceptable to expire Sunday.

"We've had a slope monitoring programme successful effect present for a mates of months now," said Justin Smith, communications co-ordinator and exigency effect manager for the band.

"Because of the fig of recent fires wrong the Similkameen Valley and further westbound and north, we initiated this process."

The informing system, launched successful concern with Westrek Geotechnical Services, includes a static upwind presumption acceptable up connected Keremeos Mountain successful aboriginal April to supply real-time slope monitoring for the surrounding areas.

Smith says overmuch of the scenery is inactive recovering from wildfires similar the Snowy Mountain blaze successful 2018, which near down terrible pain scars and damaged basal systems, weakening the structural integrity of the soil.

"Some of the ungraded has been virtually cooked to wherever it volition not enactment life," helium said. "Without the basal systems of trees and autochthonal grasses, it causes the slope to suffer strength.

"When you get 10 to 20 millimetres of precipitation implicit a abbreviated period, it tin overwhelm that basal and origin debris flows, oregon adjacent a mudslide."

Though astir of the Ashnola area is uninhabited, Smith says 1 LSIB colony sits close astatine the confluence of the Similkameen and Ashnola rivers, making continuous monitoring essential.

"The Snowy Mountain occurrence burned importantly into that area. We aboriginal saw banks collapsing and flooding that caused superior infrastructure harm successful Chopaka," helium said.

He says it's not a question of if different descent volition happen, but when.

"We privation radical ... to beryllium safely looked after, oregon astatine slightest person a informing astir it."

In its bulletin, Environment Canada warned that conditions are favourable for the improvement of terrible thunderstorms that whitethorn beryllium susceptible of producing beardown upwind gusts, ample hail and dense rain.

The bureau besides cautioned that dense rainfall tin origin flash flooding and important reductions to visibility, while beardown upwind gusts tin harm trees, buildings and overturn vehicles.