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

Flood Warnings and Advisories

Flood Warning – Salmon River
Flood Watch – Okanagan Central Interior, Similkameen
UPDATED: 1200h May 15th, 2018

The following Flood Warnings, Watches and Advisories in the Central region are in effect as of Tuesday, May 15th 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 three days has led to increased snow melt rates, and higher runoff. Another day of hot temperatures is expected on Tuesday. An upper low is forecast to bring increased chances of showers on Wednesday, and rainfall on Thursday and into Friday. Current weather forecasts are indicating that heavier rainfall amounts will be further to the east (eg. Boundary and Kootenay), however areas through the Okangan, Similkameen and Central Interior could still experience some rain. Temperatures are expected to rebuild into the long weekend.

Snowpacks are dwindling at mid-elevation and south-facing aspects, with approximately 35% 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 three days indicate that there is on-going risk for rising river levels from snowmelt this week, particularly in the Similkameen River, Salmon River, Coldwater River and downstream on the Nicola River.

There are increased risks for flood conditions through the region with rapid snowmelt and rainfall later this week. Rapid rises are possible throughout the region on Thursday and Friday, depending on rainfall amounts. For areas that do not receive organized rain, elevated risks from snowmelt may linger into the weekend.
A summary of key rivers includes:

  • Mission Creek near East Kelowna (08NM116) is flowing at approximately 68 m3/s (between a 2-year and 5-year flow) and rising. Currently forecasting indicates the potential for flows in the 100-120 m3/s range on the Thursday-Friday period, and peak levels will depend on the amount of rain the watershed receives
  • Salmon River near Salmon Arm (08LE021) is flowing at 63 m3/s (50-year flow) and slowly rising.  Currently forecasting indicates the potential for to reach similar levels experienced last week (approximately 70 m3/s), and peak levels will depend on the amount of rain the watershed receives
  • Coldwater River at Merritt (08LG010) is flowing at 78 m3/s (2-year flow) and rising. Additional rises are expected through the Thursday-Friday period, with flows up to 100 m3/s possible. Flows could exceed levels experienced last week
  • Nicola River near Spences Bridge (08LG006) is flowing at approximately 330 m3/s and rising. Additional rises are expected through the Thursday-Friday period, and flows up to 350-400 m3/s are possible. Flows could exceed levels experienced last week
  • Similkameen River near Hedley (08NL038) is flowing at approximately 515 m3/s and rising. Additional rises are expected through the Wednesday-Friday period, and flows up to 600-750 m3/s are possible. Flows are expected to exceed levels experienced last week

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