We have to
assume that this is Melbourne, Australia, and not one of the villages with that
name in Cambridgeshire, Derbyshire and South Yorkshire. In the southern
hemisphere the upper wind blows parallel to contours with low contour height on
the right. From the wind direction at Melbourne it is noted that
the contour height (and true altitude) is lower at A than it is at B and at B
it is lower than Melbourne. The contours at A are closer than at B
so the wind speed is higher at A than at B.