  Magnetic fields (MF) in the Local Supercluster (LSC) of galaxies may have
profound consequences for the propagation of Ultra High Energy Cosmic Rays
(UHECR). Faraday rotations measurements provide some informations about MF in
compact clusters. However, very few is known about less dense regions and about
the global structure of MF in the LSC. In order to get a better knowledge of
these fields we are performing constrained magnetohydrodynamical simulations of
the LSC magnetic field. We will present the results of our simulation and
discuss their implications for the angular distribution of expected UHECR
deflections.
