Why travel to northern climates when arctic air is coming your way?
High pressure and very cold air is currently moving into British Columbia.
It wants to reach us, but the mountains – the Rockies and the Cascades – are blocking it at first.
But like a side kick, there were gaps in our defence. Literally the gaps in our terrain.
And the cold attack prepares to make a successful finish to score a cold goal.
I’ll show you….
It’s cold this morning (purple and brown) in the Canadian Arctic. A drastic change in pressure is at the interface between the warm air to the south and the cold air inside.
Zooming in on the heat and wind in Washington State, at 10 a.m. this morning the state is split by the Cascades (like our politics!). Cold in the east (purple) and warmer in the west (green).
By 10 p.m. tonight, much colder air will move into southern BC (in the shade) and cooler air will push through the Fraser River valley in northern BC and into NW Washington.
At 7 a.m. Sunday, cooler air was pushing southward into the Okanagon River Valley north of central Washington, and variable arctic air was rolling into northwest Washington, as strong northeasterly winds exit the Valley. Fraser River valley.
This process continues until 10 p.m. Sunday, and if you look closely, you’ll see a northerly wind blowing into Puget Sound. Cold air is actually moving south into eastern Washington.
What about the snow tonight and tomorrow?
Precipitation has moved into the area, but it is falling to the lowlands as rain.
The total snowfall forecast to 4 a.m. from NOAA’s HRRR model shows snow in the mountains, but little in the lowlands with two outliers. (see below). The first is around Bellingham, where cold air from the Fraser Valley will support light snow, and the second is north of the Games, where the Fraser Valley currents are pushed upwards.
Between 4 a.m. Monday morning, there was more snow in Northwest Washington and a light strip of snow covered Seattle. That may involve a region of weak convergence; it totals less than 1 inch in its core. Southwest WA also saw light snowfall.
Late Sunday and Monday will be a dry but cold period.
