Running power Wind is never accounted for

I have exact same problem.Wind enabled,connected to phone for enough time to sync data from app but shows as 0.However at other times it is calculated and shows as 1.There is no pattern to this so I cant explain it.However the same problem occurs on both 645M(FW 4.0) and fenix 5 plus(FW 5.1)

I do face the same problem using the same firmware version.

This is an excerpt from Jim Vance's book "Run With Power":

"A running power meter measures exactly how hard you are working and nothing else. It ignores all other variables. A power meter doesn’t care how much sleep you got last night, how much coffee you drank this morning, how hot it is outside, how steep the hill is, if it’s windy or calm."

Let's say you want to run with your run power at 260. It doesn't matter if it's calm out or if you're running into a 15 mph head wind. If you maintain that 260 running power and encounter any of the variables mentioned above, the only thing that will change is your pace. What is Garmin trying to do with this wind setting anyway?

What Jim Vance says is not that the wind should not be counted. He only say the runner must not have to worry about external factors. But the sensor must know them to be precise.

When talking about how steep the hill is, the power sensor does includes an altimeter to measure the slope of the mountain.
The sensor includes an accelerometer to measure the force that is put in the vertical position and the force put to advance forward, during running.

The headwind is opposed to the force we put forward. The back wind adds to the force that is put forward. The sensor must know the wind to be able to know what is the force put by the wind and what is the force put by the runner.

As for the mountain. The altimeter makes it possible to determine that the road is climbing and that it is therefore more difficult for the runner to advance. It therefore takes into account this criterion in order to provide a regular power information to the runner.

I think Garmin puts the option "Wind" to possibly correct the power during a significant event on which an accurate measurement of the wind could be done, with local wind sensors. For example during a New York marathon or other very popular race. In this case it is worthwhile to equip the course with wind sensors and to indicate to the runner's Power Meters the strength of the local wind.

But if you get wind power through a very general observation, it does not work very well. That's why Garmin must probably be very conservative in this indication of wind.

Same here... I updated the local weather on my iPhone 8, sync with the FR645M via Garmin Connect Mobile App and went out for a run without my iPhone 8 and no wind information in my activity... In FW 3.70 at least was showing "Wind: 1,0", now in FW 4.10 is says "Wind: 0.0".

Someone can give me some tips about Running Power? As the FR 645M don't have an "Auto-Detect Running Power Threshold" and then set my running power zones, how can I detect my Running Power Threshold and zones? (quick test and % for each zone).