Upper level winds blow parallel to the contours, surface winds
blow across the contour lines always toward low pressure. So
this is an example of a surface wind and low pressure must be at
the bottom of the figure. The pressure gradient force always
points perpendicular to the contours toward low. The bottom
is the only one in the figure that is perpendicular to the
contours, it must be the PGF. The right most arrow is
opposite the wind so it must be the frictional force. The upward
pointing arrow is perpendicular to the wind (not exactly but
that's a drawing error). The is the Coriolis force; it is to
the right of the wind when you look downstream so this is a
northern hemisphere map.
