Some of the media are talking about a big wind event tomorrow over western Washington, and some of the amateur weather enthusiast sites have been going a bit over the top.
The truth is a bit less exciting: the winds will get gusty tomorrow afternoon, and some people may lose power, but this is not going to be a major windstorm. Gusts to 30-45 mph.
This was a difficult event to forecast earlier, with a great deal of uncertainty until today.
Why? Because we had a very small system moving directly up the coast, far harder to predict than a large cyclone moving off the Pacific. I have seen this situation many times and have learned to be careful.
The modeling systems predicted the uncertainty, something expressed by very different forecasts of the members of our ensemble forecast systems, in which we run the models many times with small differences in their initial state or model physics.
Want some inner weather "baseball"?
Yesterday, the highly skillful European Center and UKMET office models were going for much weaker winds.
The American GFS and NAM models were doing for a crazy strong event. But these are generally far less skillful for systems over the eastern Pacific. Pretty embarrassing that the U.S. models are generally inferior. Make American Weather Models Great Again!
The latest UW forecast takes a modest low-pressure system to Vancouver Island tomorrow at 4 PM (see below).
This graphic shows the sea level pressure analysis and there are a lot of pressure changes to the south of the low. That means strong winds.
Rainfall will be modest from this system (see the totals through tomorrow morning). And much of that will be snow.
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