There are occasions where live weather does not appear to work at all. This is often triggered by changing airports or aircraft at the conclusion of a flight, without backing totally out of the sim and restarting. On at least some occasions when live weather does not work at all, it may indeed be due to a loss of connection to the streamed weather data.
But when live weather is working, all other live weather parameters are consistently injected into the sim environment for users flying in US airspace, including the temperature aloft, which in all gridded weather models I am aware of, is contained in the same data parameter as wind direction and velocity (for winds aloft).
This does not appear to be an issue which only affects “some” users, nor does it only happen at “some” times. To the best of my knowledge no user of MSFS has ever experienced wind in live weather when the aircraft is positioned in the US from the beginning of the alpha to the present day.
This appears to be 100 percent correlated to the geographic position of the aircraft in the simulated world. It makes no difference which server is being used, or the time of day, nor does it depend on where the user’s computer is physically located in the “real” world.
As mentioned in my other post above, I could see the wind component of live weather instantly shutoff the moment I flew north of a certain VOR in Mexico, and the wind immediately returned when I turned the aircraft around and flew back south of the same point.
The only way to know for sure if this is being caused by a problem with missing data in the server stream would be to look at the raw stream data itself, but I know of no way to do that.
But, since surface and upper level wind is consistently present over the US on the world map, I’m quite confident that MeteoBlue is indeed sending the wind data. Whether or not the aircraft “sees” the wind seems to be totally dependent on the aircraft’s geographic position at a given time.