Flood warning now in effect for North Shore Mountains and Howe Sound

The BC River Forecast Centre upgraded its South Coast advisory to a Flood Warning at 8:30 AM on Wednesday, November 11, 2026, covering the North Shore Mountains and Howe Sound. The warning says rivers in the region have exceeded bankfull or will do so imminently, and that flooding of areas next to the affected rivers will result.

Environment Canada issued a Rainfall Warning for the Metro Vancouver North Shore, including West Vancouver and North Vancouver, at 9:35 AM on November 11, forecasting 60 to 100 mm of additional rainfall before tonight, with totals possibly near 120 mm in the mountains.

What the upgrade means

A Flood Warning is the highest level in the BC River Forecast Centre's three-step system. Under a High Streamflow Advisory, rivers rise fast but major flooding is not expected. Under a Flood Watch, rivers approach or may exceed bankfull, and flooding may occur. Under a Flood Warning, the Centre says flooding of areas next to affected rivers will result. Under a Flood Watch, flooding may occur. Under a Flood Warning, it will.

The Centre moved the South Coast from a Flood Watch to a Flood Warning in its 8:30 AM advisory on November 11. This follows a Flood Watch that was in place since November 9 and a Rainfall Warning that Environment Canada issued on November 10.

The Centre issued a separate Flood Warning for the Pemberton Valley at 8:00 AM and later moved the Kingcome River to a Flood Warning at 10:30 AM, noting both in an update to the same advisory bulletin. The South Coast warning covers the full area from Howe Sound through the Sea-to-Sky corridor, including the North Shore Mountains that sit above West Vancouver.

How much rain has fallen

The River Forecast Centre's advisory says 30 to 120 mm of rain fell across the South Coast since Tuesday. Environment Canada separately issued its Rainfall Warning at 9:35 AM on November 11, adding a forecast of 60 to 100 mm more rain until tonight for the Metro Vancouver North Shore including West Vancouver.

The advisory notes that weather models indicate a further 40 to 100 mm of rainfall through the Sea-to-Sky corridor on Wednesday. Rivers have been rising rapidly since late Tuesday night, and the Centre says levels are expected to keep rising into Thursday.

River levels recorded this morning

The River Forecast Centre's advisory reports these Water Survey of Canada real-time measurements from hydrometric gauges:

• Stawamus River at Highway 99 (gauge 08GA076): 88.6 cubic metres per second, which the advisory describes as a 2 to 5-year flow
• Clowhom River near Clowhom Lake (gauge 08GB013): 321 cubic metres per second, a 5 to 10-year flow
• Elaho River near the mouth (gauge 08GA071): 779 cubic metres per second, a 2 to 5-year flow
• Squamish River near Brackendale (gauge 08GA002): 926 cubic metres per second, approaching a 2-year flow

A 5 to 10-year flow means that level of water has historically happened about once every 5 to 10 years. The advisory notes that all of these readings reflect rivers that have been rising rapidly since late Tuesday night.

What residents should do

The River Forecast Centre's advisory gives three specific instructions for residents: stay clear of the banks of swift-running rivers, never drive across flooded roads, bridges or river crossings, and keep storm drains clear. The advisory notes that fallen leaves at this time of year can clog storm drains and affect how water flows through neighbourhoods.

North Shore Emergency Management, which covers West Vancouver, adds further detail on its flood safety page. Just 15 cm of moving water can knock a person down. The average vehicle can be swept off the road in 30 cm of moving water. NSEM advises against driving during floods and says that if driving is necessary, residents should check DriveBC first and avoid any flooded section of road.

If there is time before evacuating, NSEM says to turn off unnecessary appliances and unplug sensitive equipment, but not to shut off natural gas.

Highway 99 and roads in the warning area

Highway 99, the Sea-to-Sky Highway, runs through the full length of the area covered by the Flood Warning, from West Vancouver north through Squamish. The River Forecast Centre's advisory specifically measures the Stawamus River at the point where it crosses under Highway 99 at gauge 08GA076, where it was flowing at 88.6 cubic metres per second as of this morning.

For current conditions on Highway 99, Highway 1 and other roads, check DriveBC at drivebc.ca.

Where to get updates

The River Forecast Centre says it will provide further updates as conditions change. Its warnings page is at bcrfc.env.gov.bc.ca. Environment Canada's weather warnings for West Vancouver are at weather.gc.ca.

North Shore Emergency Management (NSEM) posts updates at nsem.ca and can be reached at 778-338-6300. The Alertable app sends emergency notifications directly to mobile phones for the North Shore. Residents can sign up at the Alertable website.