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I do understand about backing and veering wind... but I’m having a hard time with the following....
I have to be standing, facing the wind, and if I have to turn to my left to continue to face the wind... it has backed.. if I turn to face the wind to my right it’s veering...
Now surface wind will always be to the right of gradient winds.. in the sth hemisphere...I’m assuming I’m looking at the direction that the wind is travelling. So it’s blowing on my back .how is it then that gradient wind has said to have backed with respect to surface wind...because if I’m facing the winds... blowing onto my face wouldn’t I have to turn to my right from the surface wind to face the gradient wind... veering
Or have I just crossed all my winds up...
MissSoph, if it helps, I think of it this way: backing = left (anticlockwise), veering = right (clockwise). Out of a High, In to a Low.
Gradient winds happen 'higher up' than surface winds. You said "surface wind will always be to the right of gradient winds", so the opposite of that is that gradient winds will be left (backed) from the surface wind.
So I have to imagine that I’m facing in the direction of travel when referring to gradient and surface winds? P29 shows someone facing into the winds when talking about backing and veering
Oh dear.. I know you will all be sick of me.. I think I may have a the penny drop... and correct me if I’m wrong... because we talk about surface winds being below 3000’ ... That ... in my crazy reasoning... we look at the wind in the direction it is travelling... as opposed to looking into the wind.. as explained on the top of p29 of the txt?
Here is a graphic that defines a veering and a backing wind.
For an observer facing into wind as showing in the diagram, the wind is said to back if the observer has to turn "anticlockwise" to remain facing into wind. Conversely, the wind is said to veer if the same observer has to turn "clockwise" to remain facing into wind.
Notwithstanding the above, there is no requirement to face into the wind to work out if the wind is backing or veering. In the above diagram, the observer could be standing with his/her back to the wind. If the observer has to turn anticlockwise to maintain the wind on his/her back the wind is backing and vice versa.
Think of the wind velocity as the big hand of an old style analogue clock that points to the center of the clock face - assume that this clock has no little hand. If the hand moves anticlockwise on climb after takeoff the winds are said to back with altitude. Similarly on landing soon after takeoff the winds will veer on descent to land and the big hand will move clockwise back to its original direction.
Eg: If the Surface wind is 360M and the gradient wind is 300M the winds will back on departure (ie back with altitude) and veer on arrival (ie veer on descent). It all depends on how you look at it.
thank you... I get it now ...I was thrown but the facing into the wind stuff ) I think I have it all figured now.. thank you everybody for your help.. self study can be tricky.. so it’s great to have you all to ask questions of