<p>Meteotsunamis pose a serious hazard to coastal zones, as they can lead to the inundation of large areas of land and severe damage to coastal infrastructure. In addition to the direct impact of meteorological tsunami waves, the hazard can also be posed by generated or seiche oscillations. Meteorological tsunamis have virtually the same periods and spatial scales as tsunami waves and have similar impacts on the coast. Using nonlinear shallow water equations, the response of the Sevastopol bay system is studied using tsunami wave action as an example. Tsunami generation from three foci, representing underwater earthquakes with a magnitude of 7, is considered. Numerical experiments were conducted in two stages. In the first stage, the problem of tsunami wave propagation for the entire Black Sea basin was solved using the numerical model developed by the first author (see Bazykina et al. <CitationRef CitationID="CR2">2018</CitationRef>). This resulted in time series of sea level fluctuations near the Sevastopol bays. These data sets were used as forcing for the SWASH model, which describes hydrodynamic fields in the Sevastopol bay system and the adjacent sea area. After the forcing was turned off, which lasted for five hours, free oscillations in the Sevastopol bay system were simulated. Analysis of the simulation results showed that tsunamis generate intense seiche oscillations in the bays. Tsunami impacts lead to the generation of Helmholtz modes in all of the Sevastopol bays considered. Helmholtz modes of large bays penetrate into most of their neighboring bays due to coupling through the inlets. Helmholtz mode of Sevastopol Bay (with a period of approximately 50&#xa0;min) penetrate into all bays in the system. Tsunamis generate intense seiches with periods of 5–7&#xa0;min in Yuzhnaya and Kamyshovaya Bays, which can pose a potential hazard to vessels and coastal infrastructure.</p>