Re: Trajectory vs. Humidity
I would agree with the first point Charles made. I have shot thousands of rounds in rain conditions at long range and have noticed a couple of patterns:
1) Very little accuracy degradation in very light rain.
2) Shots do not hit high in medium to heavy rain, like never happens. They tend to hit low by 1/4 to 1/2 MOA at 600 yards.
3) The vertical component of wind drift is greater on left to right winds in the rain, and less on right to left winds.
4) The horizontal component of wind drift is minimized some what from what it appears relative to no rain conditions.