Forecast Triumph

Yesterday, a strong front, associated with strong winds gusting to 40 mph or more, moved through the region, resulting in numerous power outages.

As I will describe below, numerical weather models predicted this event with great skill, something we could not have done 20 years ago.   

This is a triumph of modern weather prediction technology.

Let me demonstrate this to you.  

Below is the radar image around 4 PM Saturday, based on the radar observations from the Langley Hill radar near Hoquium.  An intense radar return was apparent offshore (the thin yellow and red line, indicated by the red arrow).   This is the front.

Fronts associated with a narrow, cold frontal rainband were first described by  UW researchers, such as Professor Peter Hobbs and associates.

Even more impressive is a video of the cold front approaching the coast (from a wonderful phone app called RadarScope).

Here is a forecast of a simulated radar image, made 24 hours (from 4 PM) before the event is shown below.  It was made by the UW WRF model run by my group.  

Almost perfect.  Very strong simulated front.

A closer-in view is below.

A forecast made 60 hr before the event was virtually the same.  Strong front in the same location

A forecast made on Thursday evening, showing the strongest near-surface wind gusts, indicating strong winds over the region.  Strong enough to worry about.

The winds for Seattle made for Seattle City Light as part of the UW WindWatch system were clearly accurate, showing the threat of strong wind (the black dots are the strongest observed with the city; the gray and colored lines indicate model forecasts)

The models were very, very clear.  

There was a prediction of 30-45 mph winds over the city.  And that means power outages, particularly early in the storm season.

Such an emphatic forecast by the models was the reason I blogged about it on Friday, making it clear that some would lose power.

In fact, over 100,000 customers lost power over western Washington last night (see below).

And over 46,000 customers in Seattle lost their lights.

This kind of skillful forecasting occurs time and time again, based on highly skillful weather model forecasts.

Another reminder that it is no longer appropriate to make fun of forecasters and weather models. 

Save that for political pollsters.  😀

No longer appropriate