Snow in the Forecast?

Just a couple of days ago we hit 80 degrees at many places, followed by a thunderstorm near Deer Park yesterday. And now we’re talking about snow?

To be honest, a few of the computers were hinting at this a week ago, but I didn’t want to mention it. The computer models have really struggled with this weekend forecast. But now they’re coming into better agreement. The culprit is a deep low right over the Northwest, sending hard-to-predict bands of rain into our area. You can even see the low on radar, just west of Spokane.





Rain from this low will continue Saturday night.  Then another round of rain could spin through the area on Sunday.  Meanwhile, cold air will be moving down from Canada

The best way to view this is to look at the temperature forecast at about 5000 feet above sea level.  Here's that weather map on Saturday morning.




And here's the forecast map for Sunday evening.  Notice how much colder (bluer) things are up in Canada, as well as our area north of about I-90.


As that cold air pushes into north Idaho and northeast Washington on Sunday late afternoon and evening, snow levels will fall to at or near the valley floors in those areas.  

Here's the snowfall forecast for Sunday night from the National Blend of Models.  You can see the purple color in the mountains of northeast Washington, which represents 6-12" of snow.  Even the valleys have a light grey color, which is snowfall of less than 1".



A few things to keep in mind.  
  • The snowfall forecast graphic above doesn't take ground temperature into account.  Our ground (and especially our roads) are very warm at this time of year.  So any snow that does fall will have a hard time accumulating on the ground.
  • Aside from the unusual snow at the end of September 2019, the last time Spokane had snow in early October was on 12 October, 2001.  So accumulating snow at this early date would be highly unusual.
  • As I said earlier, the computers have been struggling with the details of this weekend event.  So it's natural to anticipate additional changes to the forecast on Sunday.
When the Canadian front pushes into the area, expect a cold northeast wind to develop and blow all Sunday night and Monday.  Winds will peak on Monday with speeds of 20 mph and gusts to 30 mph.

After the wind dies down Monday evening and Tuesday, nighttime temperatures will drop below freezing. The weather should be dry most of next week until Friday when another wet pattern sets up for the weekend.


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