How are isobars drawn?
Hello,
I was just curious as to how isobars are drawn on prog charts. I know what they mean and what you can tell by the spacing, etc. But my question is how do they know that the pressure is equal along those lines? What do they use to know where there will be a large pressure gradient in one area and a small gradient in another. My guess is that they use the altimeter settings in various metars to get a big picture, but that would only be good for a current anaylsis, not a forecast.
Thanks guys!
FlyHigh423