I use a Dwyer wind gauge to read the wind speed at the firing line. Cheap and accurate. Then use a constant for the bullet and its muzzle velocity to calculate corrections based on wind speed and directions.
Here's a table showing the wind speeds above the line of sight:
If you look at the trajectory path of a bullet, it spends only about 25% of its time at the top of its arc where wind speed's the fastest. 50% of its time in the middle wind speed range and about 25% in the lowest speed range.
The following's a table showing how much the wind has at different ranges for a given crosswind across the entire trajectory: