Weyl semimetals are recently discovered materials in which the valence and conduction bands touch at isolated points (Weyl nodes) in the Brillouin zone. This gives rise to unusual electronic properties of these materials. In particular, Weyl semimetals host surface electron states whose Fermi lines have the form of open arcs. I will show that static electric fields that are necessarily present near the crystal surface result in a spiraling structure of Fermi arcs. The winding angle of the spiral is controlled by the chirality of the Weyl node and the magnitude of the surface potential. I will also discuss magnetoresistance of a pn-junction in a Weyl semimetal.