  The first direct measurements of the HI intensity mapping power spectrum were
recently made using the MeerKAT telescope. These measurements are on nonlinear
scales, at redshifts 0.32 and 0.44. We develop a formalism for modelling
small-scale power in redshift space, within the context of the mass-weighted HI
halo model framework. This model is consistent with the latest findings from
surveys on the HI-halo mass relation. In order to model nonlinear scales, we
include the 1-halo, shot-noise and finger-of-god effects. Then we apply the
model to the MeerKAT auto-correlation data, finding that the model provides a
good fit to the data at redshift 0.32, but the data may indicate some evidence
for an adjustment at $z \sim 0.44$. Such an adjustment can be achieved by an
increase in the HI abundance or halo model bias.
