A north wind from the south

For the first time since I added a "rolling average" plot to the wind direction graph we've had a wind from the north. This, as you'll see from the image to the right, has shown up a rather obvious problem with plotting a rolling average of wind direction. Because the wind direction oscillates around 0° I end up with an average plot that suggests that the wind is coming more from the south.

D'oh! (Yes, imagine me slapping my forehead in a "it's really obvious now I see it" way)

Mostly the average plot works really well and nicely shows where the wind is generally coming from so I'm left wondering how to correct this.

Now I can see why some of the more popular weather station software plots wind direction on a radar-a-like graph.

I've been meaning to see if I can do anything with the polar plotting facility in gnuplot — this would seem to be a good enough reason as any to have a play with it and see if I can produce something sensible.

File Under: WS3600, Plots, Charts, Graphs, Wind Direction.

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