  The process of interaction between nonlinear waves on a free surface of a
nonconducting fluid in a strong tangential electric field is simulated
numerically (effects of the force of gravity and capillarity are neglected). It
is shown that singular points are formed at the fluid boundary in a finite
time; at these points, the boundary curvature significantly increases and
undergoes a discontinuity. The amplitude and slope angles of the boundary
remain small. The singular behavior of the system is demonstrated by spectral
functions of the fluid surface - they acquire a power dependence. Near the
singularity, the boundary curvature demonstrates a self-similar behavior
typical for weak root singularities.
