MAINTAINED - High Streamflow Advisory – North Coast, Central Coast, Vancouver Island (North)

UPGRADED: Flood Watch – Vancouver Island (South, East, Central, West)

MAINTAINED - High Streamflow Advisory – North Coast, Central Coast, Vancouver Island (North)

ISSUED: 7:30 AM November 27, 2021

 

The River Forecast Centre is upgrading to a Flood Watch for:

• Central Vancouver Island
• Eastern Vancouver Island
• Southern Vancouver Island
• Western Vancouver Island

The River Forecast Centre is maintaining a High Streamflow Advisory:

• North Coast including areas around Prince Rupert, Kitimat, Hartley Bay, Kemano and surrounding tributaries
• Central Coast including areas around Bella Coola, Wuikinuxv, Kingcome and surrounding tributaries
• Northern Vancouver Island

A second in a series of atmospheric rivers is impacting the British Columbia Coast through the weekend. Rainfall has begun on Vancouver Island, and rainfall warnings have been issued by Environment and Climate Change Canada for West Vancouver Island and Eastern Vancouver Island. Rainfall amounts in the 50-70 mm range are forecasted for Eastern Vancouver Island and potentially exceeding 100 mm on West Vancouver Island and potentially exceeding 130 mm around Port Renfrew. Additional snow at mid-elevations is available to melt as this system passes and is expected to add additional runoff to rivers.

Rivers are expected to see rises through Saturday and overnight into Sunday. Current precipitation forecasts and hydrologic modelling and assessments are indicating the potential for flooding in areas around the south half of Vancouver Island (south of Campbell River and Gold River) with most focused rainfall around Port Renfrew through to Cowichan Lake and the Sooke River watershed. Spillover across the Vancouver Island ranges is possible, and with the potential for flood flows onto the eastern slopes of Vancouver Island, including the Koksilah River, Chemainus River, Cowichan River, Englishman River and surrounding areas. On North Vancouver Island and the Central Coast, high streamflow is expected due to more moderate rainfalls.

An additional atmospheric river is forecast to arrive to Coastal British Columbia on Tuesday and may pose additional risk to flooding on the Central Coast and again on Vancouver Island.

The public is advised to stay clear of the fast-flowing rivers and potentially unstable riverbanks during the high-streamflow period.

Details of the COFFEE and CLEVER Model forecasts can be found at:

http://bcrfc.env.gov.bc.ca/fallfloods/map_coffee.html, and

http://bcrfc.env.gov.bc.ca/freshet/map_clever.html

The River Forecast Centre continues to monitor the conditions and will provide updates as conditions warrant.

 

A High Streamflow Advisory means that river levels are rising or expected to rise rapidly, but that no major flooding is expected.  Minor flooding in low-lying areas is possible.

A Flood Watch means that river levels are rising and will approach or may exceed bankfull.  Flooding of areas adjacent to affected rivers may occur.

A Flood Warning means that river levels have exceeded bankfull or will exceed bankfull imminently, and that flooding of areas adjacent to the rivers affected will result.