Note from the SLRD: The High Streamflow Advisory was issued by the BC River Forecast Centre and impacts all rivers, creeks and tributaries in the Howe Sound area (SLRD Electoral Area D and the District of Squamish).
High Streamflow Advisory – South Coast
ISSUED: January 26, 2018 9:00 AM
The River Forecast Centre is issuing a High Streamflow Advisory for the South Coast including:
- Howe Sound including the Stawamus River and surrounding creeks and tributaries
- Sunshine Coast including streams around Gibsons, Sechelt and surrounding areas
- North Shore Mountains including the Seymour River and surrounding creeks and tributaries
- Lower Fraser Valley including the Chilliwack River and surrounding creeks and tributaries.
An atmospheric river storm event is expected to impact the south coast of British Columbia Sunday and Monday. Rainfall amounts are forecast between 50-200mm. Freezing levels are expected to rise into the 1500-2000 m range during the storm. Snowmelt from mid-elevation terrain may add to runoff for this event. In watersheds with higher terrain, including the Squamish River and Lillooet River, snow may be the dominant form of precipitation, and river responses are expected to be lower than more coastal areas.
River levels are expected to rise rapidly in response to heavy rain. High streamflow is expected on rivers throughout the region, with the highest flows expected on Monday and possibly Tuesday.
The River Forecast Centre will continue to monitor conditions and will update the advisory as conditions warrant.
Levels of Warnings/Advisories:
High Streamflow Advisory: River levels are rising or expected to rise rapidly, but that no major flooding is expected. Minor flooding in low-lying areas is possible. This is the lowest level of advisory.
Flood Watch: River levels are rising and will approach or may exceed bankfull. Flooding of areas adjacent to affected rivers may occur. This is the intermediate level of advisory.
Flood Warning: River levels have exceeded bankfull or will exceed bankfull imminently, and that flooding of areas adjacent to the rivers affected will result. This is the highest level of advisory..