  We estimate photospheric velocities of Type II-P supernovae using model
spectra created with SYNOW, and compare the results with those obtained by more
conventional techniques, such as cross-correlation, or measuring the absorption
minimum of P Cygni features. Based on a sample of 81 observed spectra of 5 SNe,
we show that SYNOW provides velocities that are similar to ones obtained by
more sophisticated NLTE modeling codes, but they can be derived in a less
computation-intensive way. The estimated photospheric velocities (v_model) are
compared to ones measured from Doppler-shifts of the absorption minima of the
Hbeta and the FeII \lambda5169 features.
  Our results confirm that the FeII velocities (v_Fe) have tighter and more
homogeneous correlation with the estimated photospheric velocities than the
ones measured from Hbeta, but both suffer from phase-dependent systematic
deviations from those. The same is true for comparison with the
cross-correlation velocities. We verify and improve the relations between v_Fe,
v_Hbeta and v_model in order to provide useful formulae for
interpolating/extrapolating the velocity curves of Type II-P SNe to phases not
covered by observations. We also discuss the implications of our results for
the distance measurements of Type II-P SNe, and show that the application of
the model velocities is preferred in the Expanding Photosphere Method.
