Flood Warnings and Advisories
High Streamflow Advisory: South Coast
ISSUED: February 14 2017 11:00AM
The BC River Forecast Centre is issuing a High Streamflow Advisory for the South Coast including:
- Howe Sound, including the Stawamus River and surrounding creeks
- North Shore, including the Seymour River, Coquitlam River and surrounding creeks
- Fraser Valley, including the Chilliwack River and surrounding creeks
- Sunshine Coast, including creeks in the Gibsons and Sechelt areas
A strong Pacific storm is expected to spread heavy rain across the South Coast Wednesday evening and through the day on Friday. Rainfall amounts up to 100mm, and potentially more over higher terrain, are expected by Thursday morning. Temperatures are expected to remain high throughout this event, with freezing levels generally above local mountain top level. In addition to heavy rainfall, melt of snow in low elevation areas is also expected, and will contribute to streamflow runoff. At high elevations, deeper snow will be able to absorb much of the rain and energy from the warm temperatures.
High streamflow is expected throughout the region on Wednesday, and potentially into Thursday morning. At this point, forecasts are not indicating the potential for rivers to reach flood stage, however low-lying areas may experience minor flooding. With snow at low elevations, minor flooding is also possible in areas with poor drainage or where drainage is impeded by snow.
The public is cautioned to stay clear of rivers and riversides during the high streamflow period because the quickly flowing water and the adjacent riverbanks are potentially unsafe.
The River Forecast Centre will continue to monitor weather and streamflow 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.