Wow, definitely feeling the love here :-(
I did a google search and found a bunch of crap all over the place. I hoped someone here would give me something a little more "tried and true."
I know of wind meters (actually called anemometer) but I again hoped that someone could provide something like, "If your puff of chalk dust floats 5 feet away from you in 1 second the wind is going 5 mph." Or something like that.
Just guessing could mean being off by 10+ inches on a 400 yard shot for a barely imperceptible breeze.
Anyone else want to chime in...hopefully taking it up a notch or two?