  Chynoweth and Sewell proposed a mathematical model for an atmospheric front
based on the singularities of the Legendre transformation between different
pairs of dual variables. Drawing inspiration from their work, we formalize the
idea of a Chynoweth-Sewell front and illuminate its geometrical meaning from
the viewpoint of Monge-Ampere geometry. This extends our previous work on the
semigeostrophic model to dynamically-forming singularities. We use the notion
of a Chynoweth-Sewell front to characterize the classical Eady problem and its
known solutions in geometrical terms.
