  The influence of the atomic-scale inhomogeneities of the pairing interaction
strength on the superconducting order parameter and the conductance spectra
measurable by STM is studied in the framework of weak-coupling BCS-like theory
for two-dimensional lattice model. First of all, it is found that the
inhomogeneity having the form of atomic-scale regions of enhanced pair
interaction increases the ratio of the local low-temperature gap in
differential conductance spectra to the local temperature of vanishing the gap
$2\Delta_g/T_p$. Even in the framework of mean-field treatment this ratio is
shown to be larger than the one corresponding to the homogeneous case. It is
shown that the effect of thermal phase fluctuations of the superconducting
order parameter can further increase this ratio. Taking them into account in
the framework of a toy model we obtained the ratio $2\Delta_g/T_p$ to be $\sim
7-8$. It is found that the additional atomic-scale hopping element disorder and
weak potential scatterers, which can also take place in cuprate materials, have
no considerable effect on the statistical properties of the system, including
the distribution of the gaps, $T_p$ and the ratio $2\Delta_g/T_p$. The second
consequence of the atomic-scale order parameter inhomogeneity is the
anticorrelation between the low-temperature gap and the high-temperature
zero-bias conductance. The obtained results could bear a relation to recent STM
measurements.
