To be fair, Seattle's city fathers and those who headed for the mountains completely failed to predict it too, and NOAA makes the data they gather publicly available.

I recall being advised to always take tire chains with me if I were driving above 5000ft in the winter in So Cal because "You never know when it might snow", so I did.



Forecasts are made to help inform a decision. That's all.

If I lived there I would have still brought my tire chains if I were driving up into the mountains, but if they predicted it would almost certainly dump snow I probably would not have gone.