At longer ranges, the wind at your position may be wildly different from what the bullet is experiencing. Take your best guess on the first shot, then let the bullet's impact give you feedback. Measure the distance between where you held and where it hit, and look up the full value drift for that range. Determine the wind value from there and try holding that the next shot.

First round hits at long ranges or small targets are very difficult unless someone has already told you what the wind is doing.