  Gravitational-wave (GW) data contains non-Gaussian noise transients called
"glitches". During the third LIGO-Virgo observing run about 24% of all
gravitational-wave candidates were in the vicinity of a glitch, while even more
events could be affected in future observing runs due to increasing detector
sensitivity. This poses a problem since glitches can affect the estimation of
GW source parameters, including sky localisation, which is crucial to identify
an electromagnetic (EM) counterpart. In this paper we present a study that
estimates how much sky localisation is affected by a nearby glitch in low
latency. We injected binary black hole (BBH), binary neutron star (BNS) and
neutron star-black hole (NSBH) signals into data containing three different
classes of glitches: blips, thunderstorms and fast scatterings. The impact of
these glitches was assessed by estimating the number of tile pointings that a
telescope would need to search over until the true sky location of an event is
observed. We found that blip glitches affect the localisation of BBH mergers
the most; in the most extreme cases a BBH event is completely missed even by a
20 deg$^2$ field-of-view (FOV) telescope. Thunderstorm glitches have the
biggest impact on BBH and NSBH events, especially if there is no third
interferometer, while BNS events appear to be not affected. Fast scattering
glitches impact low latency localisation only for NSBH signals. For
two-interferometer network small (FOV=1 deg$^2$) and large (FOV=20 deg$^2$)
telescopes are affected, whereas three-interferometer localisation bias is
small enough not to affect large (FOV=20 deg$^2$) telescopes.
