  We study the effect of superconducting fluctuations on the tunnel
current-voltage characteristics of disordered superconducting films placed in a
perpendicular magnetic field, $H$, in the whole $H$-$T$ phase diagram outside
the superconducting region. This tunnel-current is experimentally accessible by
STM measurements. In the domain of temperatures $T\geq T_{c0}$ and relatively
weak fields $H\ll H_{c2}(0)$ we reproduce existing results for the zero-voltage
tunneling conductance, but also discover an important nonlinear contribution,
which appears due to dynamic fluctuation modes and results in the formation of
a strong zero-bias anomaly (ZBA) on the scale $eV\sim
k_{\mathrm{B}}(T-T_{c0})$. At large voltages ($eV\sim k_{\mathrm{B}}T_{c0}$)
these modes, together with the contribution from static fluctuations, form a
pseudogap maximum. At low temperatures, with magnetic field values near
$H_{c2}(0)$, fluctuations acquire quantum character and the general picture of
the voltage dependent tunneling conductance resembles that one close to
$T_{c0}$, where the role of temperature and magnetic field are exchanged. In
particular, a gap-like structure appears with maximum at $eV_{\max}\sim
\Delta_{\mathrm{BCS}}$ and a sharp ZBA on the scale $eV\sim
\Delta_{\mathrm{BCS}}(H/H_{c2}(0)-1)$. The complete expression for the
tunneling current at arbitrary fields and temperatures can be evaluated only
numerically, which is presented in detail.
