Wed. Jun 26th, 2019

High Streamflow Advisory Issued

  • Vancouver Island Inland Sections Forecast - No watches or warnings in effect.

    Forecast Issued 11:00 AM PDT Wednesday 26 June 2019 - Wednesday: A mix of sun and cloud. 30 percent chance of showers this afternoon with risk of a thunderstorm. High 24. UV index 7 or high. Wednesday night: Partly cloudy with 30 percent chance of showers. Rain beginning before morning. Risk of a thunderstorm early this evening. Low 11. Thursday: Rain. High 14. UV index 2 or low. Thursday night: Cloudy with 60 percent chance of showers. Low 9. Friday: Cloudy. High 20. Friday night: Cloudy periods. Low 9. Saturday: Sunny. High 23. Saturday night: Clear. Low 10. Sunday: Sunny. High 24. Sunday night: Cloudy periods. Low 12. Monday: A mix of sun and cloud. High 22. Monday night: Cloudy periods. Low 13. Tuesday: A mix of sun and cloud. High 22.

  • Current Conditions
    24.0° C
    1.0 ° C/hr
    100.92 kPa
    NE 6.4 km/h
    gusting 20.9 km/h
    40 %
    Rain Rate
    0.0 mm/hr
    Wind Chill
    24.0° C
    Heat Index
    24.0° C
    9.6° C
    915 W/m2
    Last Updated: 15:55:00 PST
    Click to Refresh or See All Conditions
  • Day Almanac
    Day's Rain
    0.0 mm
    Day ET
    0.0 mm mm
    Rain Storm
    NotAvailable mm
    Civil Rise
    Moon Phase
    Last quarter (35% full)
    Civil Set
    Day Length
    Day High
    24.0° C @ 15:53 Tdy.
    Day Low
    10.0° C @ 05:44 Tdy.
    Day High Rain Rate
    Day High Barometer
    101.29 kPa @ 06:58 Tdy.
    Day Low Barometer
    100.92 kPa @ 15:44 Tdy.
    Day Low Windchill
    10.0° C @ 05:44 Tdy.
    Day High Heat Index
    24.0° C @ 15:53 Tdy.
    Day High Wind Gust
    S 14.8km/h @ 15:05 Tdy.
    Day High Solar Radiation
    1195W/m2 @ 12:28 Tdy.
    Day High UV Index
    6.5 @ 12:28 Tdy.

See the previous post for details on the rain.  I will update this post if there is anything else significant that changes.

The River Forecast Centre has issued a High Streamflow Advisory for our region. You can see updates directly here.

The Current Advisory (Nov 21 1:41PM)

High Streamflow Advisory – Vancouver Island
ISSUED: November 21, 2017 10:15 AM

The River Forecast Centre is issuing the High Streamflow Advisories for:

  • Central Vancouver Island including Sproat River, Somass River and tributaries and areas around Port Alberni
  • Eastern Vancouver Island including the Englishman River, Tsolum River, Oyster River and tributaries around Campbell River, Comox, Parksville and surrounding areas
  • Southern Vancouver Island including the Chemainus River, Cowichan River, Koksilah River and surrounding areas

A storm cycle is expected to impact Vancouver Island over the Tuesday to Thursday period. Heavy rainfall is expected, particularly over the Tuesday to Wednesday period.  Rainfall totals are forecasted to be in the 100-150 mm range, with the potential for higher amounts where upslope conditions occur, and lower amounts along the eastern slopes of Vancouver Island. Temperatures are expected to rise sharply through Tuesday, with freezing levels approaching 3000m. Snowmelt is expected to contribute to river runoff during this storm event.

River levels are expected to rise through Tuesday, with peak levels expected on Wednesday or potentially into Thursday. Current modelling is indicating the potential for rivers to reach up to approximately 2-year return period flows, or similar levels that were experienced last weekend. On the Somass River, flows are currently forecasted to reach up to 5-year return period levels, or higher than was experienced this past weekend (e.g. similar levels to the November 2016 event). High tides and a moderate storm surge are expected through the week, particularly on Thursday, and may exacerbate river levels at river outlets.

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