# Forums

Help › Forums

#### Cross Wind Calculations

Mon, Jun 27 2022 1:18 AM (109 replies)
•  RobertoPro 110 Posts Sat, May 4 2013 11:49 AM

I would like as many comments as I can get:

A 10 MPH crosswind (3 or 9 o'clock) will move 10 feet right or left per 100 yards.

Therefore, a 10 MPH crosswind will mover 20 feet at a distance of 200 yards.

All other distances and angles to the wind are proportional.

•  courteneyfish 15,796 Posts Sat, May 4 2013 9:45 PM

There are lots of variables with all winds both here and in real life, no fixed calculation would work for every shot. If it were fixed than any person with a calculator could nail it and we'd all be shooting 50's.

•  SHRUDE 5,835 Posts Sat, May 4 2013 9:56 PM

RobertoPro:
A 10 MPH crosswind (3 or 9 o'clock) will move 10 feet right or left per 100 yards.

Hmm not really. Thats usually a wedge shot and i tend to ignore the wind fairly much on a wedge shot.  The pin is 6ft tall so i might allow 1 - 2ft for this wind here.

however,

RobertoPro:
a 10 MPH crosswind will mover 20 feet at a distance of 200 yards.

Wind will certainly affect your trajectory  over this kind of distance. I dont know if it will affect it THAT much though.  I maymiss the ding into the wind to keep my balls flight straight.

And as Courteney has said, then there are many variables, the club and shot you use..  the actual course may have less wind affect.

Best to take notes on all the courses. Note wind effect and the lie of the green on approaches.

But some players much better than I, have calculations for the wind down. Search the forums for some of these guru's

•  bubbadork 984 Posts Sun, May 5 2013 7:57 AM

The effect of the wind will vary according to the trajectory of the ball and the spin on the ball as well as the frontal area of the ball. I don't know if WGT deviates each of those variables or if they just deviate the total effect. I do know they deviate the wind as well as the position within the circle of precision (or forgiveness).

•  ApexPC 3,164 Posts Sun, May 5 2013 8:16 AM

Ball size is regulated by the RoG, so the ball frontal area is essentially a constant.

Based on my experiences I agree with the OP's assessment, at least as a basic rule of thumb. One has to look closely at the wind direction indicator, and no doubt, a lower ball trajectory decreases the effect of the wind.

In a 10 mph 90° cross wind, at 100 yards the ball will be blown 10 feet left or right of the aiming point.

So a 75 yard wedge shot will move left or right 7.5 feet , and a 300 yard tee shot will move 30 feet left or right.

For wind angles on a diagonal, I find using 75% of the wind speed for a 45° angle more accurate than 50%.

Then you need to figure out a way to accurately determine where left or right of the point you want the ball to land that you aim for by moving the aiming point or by using the early/late ding method.

I often use the aiming point box. From many of the alternate views in front of and behind the green, I have found the width of the box to be about equal to 10 feet.

Some of those view are from further away from the green, and I adjust my assumption of how wide the aiming box represents accordingly.

I multiply the wind speed by the shot distance after adding a hundredths decimal point to the distance.

If I have a 90°, 13 mile an hour wind and a shot distance of 182 yards, I multiply 13 x 1.82 = 23.66 feet that the ball will be blown sideways.

If I have a 90°, 13 mile an hour wind and a shot distance of 67 yards, I multiply 13 x .67 = 8.71 feet that the ball will be blown sideways.

•  bubbadork 984 Posts Sun, May 5 2013 10:40 AM

The 45 degree angle actually represents a factor of .707, so your 75% is much better than 50%.

I find, experimentally, that the side component of the force is not the same as the forward component of the force. I attribute that to lift. I also find, experimentally, that the force is not linear with respect to wind velocity. I attribute that to the fact that acceleration is proportional to the square of the velocity.

Take my attributions with a grain of salt. My physical equation for ball flight agrees very closely with results on WGT until I add wind to the equation. Then it differs (not hugely, but significantly). That's why I use experimental data from the course instead of my model.

•  courteneyfish 15,796 Posts Sun, May 5 2013 11:17 AM

It just seems strange that all these people with fancy calculations don't have good stats.

•  bubbadork 984 Posts Sun, May 5 2013 12:39 PM

One reason would be putting.

•  ApexPC 3,164 Posts Sun, May 5 2013 1:07 PM

courteneyfish:

It just seems strange that all these people with fancy calculations don't have good stats.

I'm old and have trouble hitting the ding! on every shot.

•  Steven1163 2,912 Posts Sun, May 5 2013 2:11 PM

What about elevation? how will a drop or rise in this affect ur windage figuring? Myself i dont wanna sit and calculate all this.....i usually just use my best judgement.....and from past shots i have stored away in my mind....