With the geostrophic wind
associated with straight, parallel isobars the pressure gradient force (PGF) is
balanced by coriolis force.
Coriolis
=2ωρVSinLat where
ω =rate of rotation
of the Earth, ρ =air density and V = wind speed
So PGF = 2ωρVSinLat
therefore V = . PGF .
2ωρSinLat
Wind speed varies
directly with pressure gradient force and inversely with the rate of rotation of
the Earth, air density and the sine of latitude.