We calculate semianalytically the distance to the heliospheric termination shock, and we use Ulysses measurements as data input for a realistic application. Therefore, we can find directly the consequences of the solar wind latitudinal variation on the shape of the termination shock. The model that we use is an approximate gasdynamic model. Our purpose is to develop a semianalytical model that can use any spacecraft measurements as data input to give the distance of the termination shock from the Sun, avoiding the complicated but more accurate numerical simulations.