  We present results from three-dimensional (3-D) numerical simulations
investigating the magnetohydrodynamics of cloud-wind interactions. The initial
cloud is spherical while the magnetic field is uniform and transverse to the
cloud motion. A simplified analytical model that describes the magnetic energy
evolution in front of the cloud is developed and compared with simulation
results. In addition, it is found the interaction of the cloud with a
magnetized interstellar medium (ISM) results in the formation of a highly
structured magnetotail. The magnetic flux in the wake of the cloud organizes
into flux ropes and a reconnection, current sheet is developed, as field lines
of opposite polarity are brought close together near the symmetry axis. At the
same time, magnetic pressure is strongly enhanced at the leading edge of the
cloud from the stretching of the field lines that occurs there. This has an
important dynamical effect on the subsequent evolution of the cloud, since some
unstable modes tend to be strongly enhanced.
