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

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

    Forecast Issued 4:00 PM PDT Monday 23 April 2018 - Monday night: Partly cloudy. Low plus 4. Tuesday: Mainly cloudy. High 20. UV index 4 or moderate. Tuesday night: Clearing in the evening. Low plus 5. Wednesday: Sunny. High 24. Wednesday night: Clear. Low 6. Thursday: Sunny. High 26. Thursday night: Clear. Low 7. Friday: A mix of sun and cloud. High 20. Friday night: Cloudy periods. Low 8. Saturday: A mix of sun and cloud. High 16. Saturday night: Cloudy periods. Low 7. Sunday: A mix of sun and cloud. High 15.

  • Current Conditions
    Temperature
    6.6° C
    -0.8 ° C/hr
    Barometer
    102.51 kPa
    0.0
    Wind
    N/A 0.0 km/h
    gusting 0.0 km/h
    Humidity
    78 %
    Rain Rate
    0.0 mm/hr
    Wind Chill
    6.6° C
    Heat Index
    6.6° C
    Dewpoint
    3.0° C
    UV
    0.0
    Solar
    0 W/m2
    Last Updated: 1:35:00 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
    05:34
    Moon Phase
    First quarter (66% full)
    Civil Set
    21:01
    Day Length
    13:17:17
    Day High
    8.2° C @ 00:00 Tdy.
    Day Low
    6.6° C @ 01:30 Tdy.
    Day High Rain Rate
    0.0mm/hr00:00
    Day High Barometer
    102.51 kPa @ 00:58 Tdy.
    Day Low Barometer
    102.49 kPa @ 00:00 Tdy.
    Day Low Windchill
    6.6° C @ 01:30 Tdy.
    Day High Heat Index
    8.2° C @ 00:00 Tdy.
    Day High Wind Gust
    S 0.0km/h @ 00:05 Tdy.
    Day High Solar Radiation
    0W/m2 @ 00:00 Tdy.
    Day High UV Index
    0.0 @ 00:00 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!