Flood Warnings and Advisories - River Forecast Centre - Province of British Columbia

Flood Warnings and Advisories

Flood Warning – Salmon River
Flood Watch – Shuswap River (NEW) Okanagan Central Interior, Similkameen
High Streamflow Advisory – North Thompson (NEW), Thompson River (NEW)
UPDATED: 1200h May 18th, 2018

The River Forecast Centre is ISSUING a Flood Watch for:

  • Shuswap River

The River Forecast Centre is ISSUING a High Streamflow Advisory

  • North Thompson River and tributaries including the Clearwater River
  • Thompson River near Spences Bridge

The following Flood Warnings, Watches and Advisories in the Central region are in effect as of Friday, May 18th 1200hr:

  • Flood Warning – Salmon River near Falkland and Salmon River near Salmon Arm
  • Flood Watch – Okanagan including Mission Creek and tributaries in the Vernon, Kelowna, Penticton, Oliver and surrounding areas
  • Flood Watch – Similkameen River and tributaries including the Tulameen River
  • Flood Watch – Central Interior including the Nicola River, Coldwater River, Bonaparte River, Guichon Creek and tributaries in the Merritt, Kamloops, Cache Creek and surrounding areas

High temperatures over the past week has led to increased snow melt rates and higher runoff. Temperatures were cooler yesterday as an upper low moved through the region bringing increasing cloudiness and some showers.  The showers did not have noticeable effects on the flows in the region.  There is still a risk of further showers or thunderstorms in the next few days in the Okanagan, Similkameen, South Thompson, but the likelihood is the rainfall will be localized and not widespread.  Temperatures are expected to increase starting on Monday and become very warm by mid next week.

Snowpacks are dwindling at mid-elevation and south-facing aspects, with approximately 10% of snow remaining at the Greyback Reservoir automated snow weather station. At higher elevations, 60-80% of the annual snowpack remains.

High melt rates over the past week gradually increased flows in the Similkameen River, Salmon River, Mission Creek, Coldwater River and downstream on the Nicola River.  Cooler temperatures yesterday dropped flows in these watersheds overnight.  The likelihood of these rivers flooding from only snowmelt contributions has now dissipated, and the ongoing risk is associated with widespread rainfall.

The Shuswap River has increased considerably in the past week due to increased releases from BC Hydro at Sugar Lake Dam.  The releases have increased the Shuswap River downstream near Lumby and Enderby.

A summary of key rivers includes:

  • Thompson River near Spences Bridge (08LF051) is flowing at 3,170 m3/s (5-year flow) and rising.  Current forecasts indicate the river to continue rising through the weekend and reach approximately 3500 m3/s (10-year) at the start of next week
  • North Thompson River at McLure (08LB064) is flowing at 2,200 m3/s (5-year flow) and beginning to level.  It is likely the flows will remain fairly steady over the weekend and could rise further due to warm weather next week
  • Shuswap River near Lumby (08LC003) is flowing at 335 m3/s (10-year flow) and rose considerably due to the releases from Sugar Lake Dam.  Flows are expected to stay fairly steady over the next few days
  • Shuswap River near Enderby (08LC002) is flowing at 470 m3/s (5-year flow) are continuing to rise.  Flows are expected to surpass the 2012 peak and reach 520 to 550 m3/s into next week
  • Mission Creek near East Kelowna (08NM116) is flowing at approximately 51 m3/s (below a 2-year) and dropped overnight from cooler temperatures
  • Salmon River near Salmon Arm (08LE021) is flowing at 55 m3/s (20-year flow) and dropped overnight from cooler temperatures
  • Coldwater River at Merritt (08LG010) is flowing at 66 m3/s (below a 2-year flow) and dropped overnight from cooler temperatures
  • Nicola River near Spences Bridge (08LG006) is flowing at approximately 277 m3/s (5-year flow) and dropped overnight from cooler temperatures
  • Similkameen River near Hedley (08NL038) is flowing at approximately 470 m3/s and dropped overnight from cooler temperatures

The River Forecast Centre will continue to monitor conditions and update this advisory as conditions warrant.

Contact:
Media relations,
Ministry of Forests, Lands, Natural Resource Operations and Rural Development
Tel: 250 356-7506

Levels of Warnings/Advisories:

  1. 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.
  2. Flood Watch: River levels are rising and will approach or may exceed bankfull. Flooding of areas adjacent to affected rivers may occur.
  3. Flood Warning: River levels have exceeded bankfull or will exceed bankfull imminently, and that flooding of areas adjacent to the rivers affected will result.

Links:

  1. Home of River Forecast Centre
  2. Current Streamflow Conditions and Flood Forecast Modeling
  3. Map of Current Streamflow Return Periods for All WSC Stations
  4. CLEVER Model 10-day Forecasts of Discharges and Return Periods
  5. COFFEE Model 5-day Forecasts of Discharges and Return Periods
  6. Back to page of Flood Warnings and Advisories