A local dust storm was observed near the Viking Lander 1 site by Viking orbiter 1 in September, 1977, when the areocentric longitude of the sun, Ls, was 340¿ (shortly before vernal equinox). The orbiter observations, which consisted of a time sequence of pictures, show that the storm moved at about 50 m/sec to the ENE from the Lunae--Planum region into the Chryse basin. Both baroclinic waves and topography may have been associated with the generation of the storm.