Rain then Flurries in transition. Snow dumps possible East/South Island

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

    Forecast Issued 05:00 AM PDT Sunday 22 July 2018 - Sunday: Sunny. High 31. Humidex 33. UV index 8 or very high. Sunday night: Clear. Low 13. Monday: Sunny. High 32. Humidex 33. Monday night: Clear. Low 13. Tuesday: Sunny. High 34. Tuesday night: Clear. Low 13. Wednesday: Sunny. High 35. Wednesday night: Clear. Low 13. Thursday: Sunny. High 34. Thursday night: Clear. Low 14. Friday: Sunny. High 29. Friday night: Clear. Low 15. Saturday: Sunny. High 29.

  • Current Conditions
    Temperature
    14.8° C
    2.1 ° C/hr
    Barometer
    102.38 kPa
    0.0
    Wind
    N/A 0.0 km/h
    gusting 0.0 km/h
    Humidity
    83 %
    Rain Rate
    0.0 mm/hr
    Wind Chill
    14.8° C
    Heat Index
    14.8° C
    Dewpoint
    11.9° C
    UV
    0.6
    Solar
    120 W/m2
    Last Updated: 7:35:00 PDT
    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
    04:57
    Moon Phase
    First quarter (77% full)
    Civil Set
    21:52
    Day Length
    13:25:41
    Day High
    17.4° C @ 00:00 Tdy.
    Day Low
    12.4° C @ 06:05 Tdy.
    Day High Rain Rate
    0.0mm/hr00:00
    Day High Barometer
    102.38 kPa @ 07:14 Tdy.
    Day Low Barometer
    102.3 kPa @ 00:00 Tdy.
    Day Low Windchill
    12.4° C @ 06:05 Tdy.
    Day High Heat Index
    17.4° C @ 00:00 Tdy.
    Day High Wind Gust
    S 0.0km/h @ 00:25 Tdy.
    Day High Solar Radiation
    127W/m2 @ 07:35 Tdy.
    Day High UV Index
    0.6 @ 07:25 Tdy.

Before I get to the cold and snow and whatnot, let’s talk about Friday.

It is already showery out there, you can expect showers on and off all day. The models show the first shot of serious rain will start around 5-6PM.
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That rain will last through the night but should dry up a bit on Saturday. The fun and intrigue begins on Sunday. What I will do now is turn it over to Environment Canada’s special weather statement, and augment their words with pictures. I will leave out the parts about the North Coast.

Warning Statement

Arctic air to reach the BC coast…
A major change in the weather pattern will occur this weekend and Monday. The change will take place in two steps – the arrival of a Pacific front followed by an Arctic front.
….
The Pacific front will cross the South Coast on Sunday night.

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In the cool moist unstable air behind this system rain showers may turn to snow flurries – even at sea-level.
In this scenario, the intensity of the rain is important: the air will cool near heavy rainshowers and this cooling may prompt a local phase-change from rain to snow with local accumulations of a few centimetres.

Chris says: This scenario is the most likely one to cause snowfall in the Alberni Valley, but is also the most difficult to predict.
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Late Monday the Arctic air will begin draining out of the South Coast mainland inlets. Residual moisture from the previous front may result in a brief period of snowflurries and local accumulations of a few centimetres. Again, with strong winds accompanying the flurries, local white-out conditions are possible in some preferred locations on the South Coast: Sumas Prairie in the Fraser Valley, Howe Sound and possibly the East Coast of Vancouver Island if the Arctic ‘push’ is strong enough.

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By Tuesday morning the South Coast will be bathed in brilliant sunshine but the windchills will continue as usual in the Fraser Valley Howe Sound and the East Coast of Vancouver Island. Right now it appears the brilliant but cold conditions will persist through next week as another blocking ridge sets up over the Pacific. However an Arctic outbreak often leads to significant snowfall events on the BC coast.

And that’s all Environment Canada has to say for now. Stay tuned through the weekend. What is a sure thing at this point is the cold air is coming. What will make all the difference is how fast it comes and how much moisture is lingering, and how much instability there is on the East Coast for big snowfall, before everything dries out and it turns sunny.

Keep your eye on Facebook, Twitter, and this blog as I will update it tomorrow and Sunday too.

Fingers crossed for some fun, but safe, winter weather!