The modulated vortex model introduced by Zabusky and McWilliams [Phys. Fluids25, 2175 (1982)] is applied to a cylindrical plasma to study dynamical behavior of a many‐vortex system. Anticyclones are shown to be long lived while cyclones are dissolved into the core and outer dresses which are left behind the core. This observation is in good agreement with the experimental results by Antipovetal. [Sov. J. Plasma Phys.14, 648 (1988)].