Environment Canada has issued severe storm warnings with the possibility of strong winds, heavy hail and heavy rains in parts of southern British Columbia.
The weather agency says the clock is in effect in the Boundary, Nicola, Shuswap and South Thompson regions.
The Fraser Canyon, including Lillooet, and the Okanagan Valley, including Kelowna, Vernon, and Penticton, are also included in the clock.
The BC River Forecast Center has issued a high flow warning for the southern interior and southeastern part of the province, including the Similkameen River, Okanagan and Mission Creek, Boundary, east and west of Kootenay and its tributaries.
A high flow warning means river levels are rising or expected to rise rapidly, but no major flooding is expected.
He says there is potential for heavy rains and thunderstorms in the southern interior and Kootenays on Sunday and Monday, and rivers are expected to grow in the areas receiving the heaviest showers.
The center says that, given the uncertainty about the exact locations and intensity of the rains, it is possible that small and medium-sized watersheds across the region may experience high flows on Monday and Tuesday.
A flood warning, first issued on June 27, remains in effect for Quesnel. A warning means floods are forecast.
Meteorologists say people should stay indoors during a storm and avoid riverbanks when there are warnings.