B.C.'s snowpack doubled in 14 days, another 50+ cm coming
Meteorologist
Wednesday, January 31, 2018, 6:15 AM - After some heroic rescues on Vancouver Island, stream flows peaked on Monday and the flood risk diminishes for the rest of this week. We’re entering a period of weather that can give a higher confidence in our upcoming pattern.
Computer models handle a well amplified (jet stream featuring large ridges and troughs) better—than say a strong pacific zonal flow over North America. The main features slow down and this predictability we can use to our advantage. Over the next seven days, a general northwest flow with seasonal temperatures and a continuation of alpine snow.
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But first, a ski season check-in.
The past two weeks have been an incredible stretch for the B.C. mountains. How impressive? A faster increase than the price of Bitcoin?
Let’s head up to 1400 metres in the heart of Vancouver Island where snowfall is measured in metres, not centimetres:
Yes, you’re viewing that graph right. In less than 14 days, we’ve doubled our snowpack for the entire 2017-2018 ski season.
A snow pillow (snow measurement station) on Vancouver Island shows the explosive growth we’ve experienced with snow accumulation the alpine, along with the rise of serious avalanche risk—even within resort boundaries.
In fact, over 80% of the snow accumulation we’ve seen this year occurred within two relatively short bursts totaling about four weeks at the end of November and mid-January. La Nina is known for epic dumps of snow for the Pacific Northwest as cool air remains locked up in the continent while an active jet stream ushers in waves of moisture.
But, what’s next? I want to take a look at a snap-shot of conditions to finish off this week.
A different approach is looking at the predicted long-wave radiation, which can project cloud patterns and can be used as a good proxy for what satellite imagery may look like in the future.
Don’t expect blue skies and a lack of precipitation, the high pressure is projected to remain well to our south.
Systems over the next few days will be directed over a building ridge crossing over much of the Pacific Northwest. This ridge of high pressure will further amplify this weekend, which will attempt to ease precipitation over the region. Showery conditions are still to be expected, but no major low pressures are expected to impact B.C. in the short-term.
Meanwhile, some of the coldest air in the world is set to build in across North America, east of the Rockies.
The exclamation mark above indicates another 50+ cm in the alpine regions of Vancouver Island and the Coastal Mountains this week—lesser amounts for the Columbia and Rocky mountains. The question mark represents the potential for snow to spill across into Alberta as early as Friday evening—really putting in a dent in Edmonton’s snow drought.
Long range for B.C. for the first full week of February includes a drying trend with a cool northwest flow over the province with weak waves tracking in from the Gulf of Alaska. These weaker systems will provide nice top-ups and fresh powder for the ski hills and isolated showers and periods of rain with several breaks along coastal sections.
Check back for updates as we continue to monitor the forecast.
