By analysis of leveling data, a large area in southern California was identified as having uplifted between 1960 and 1974; the pattern and magnitude of the apparent movement were first discussed by Castle et al. (1976). The uplift zone included 12,000 km2 with the maximum vertical movement of 25 cm centered near Palmdale, Castle (1978) later increased the estimate of uplift at Palmdale to 35 cm. The pattern of uplift was constructed by reviewing profiles of repeated levelings. After field experiments confirmed that the southern California leveling data were contaminated by refraction errors, Holdahl (1981) developed a temperature stratification model to enable retroapplication of Kukkamaki's refraction correction to the affected data. Vertical motion in the Palmdale region has not been reassessed by simultaneous least squares adjustment of the networks formed by the corrected observations. The new results show 7.5¿4.0 cm of apparent upward movement at Palmdale. Part or all of the 7.5 cm might be attributable to residual systematic error. The great concern associated with Palmdale, if based on motion calculated from leveling data, does not seem warranted. Castel's original result was strongly influenced by a single level route to Palmdale. Refraction error accumulates rapidly on this route because of the long gentle slope and the location of sightings over railroad ballast where vertical temperature gradients are unusually large. Perhaps more important than the existence of the Palmdale Bulge is the question of whether large aseismic vertical motions of entire regions can actually occur in a short time span. The Palmdale Uplift is often referred to as a good example of this type of motion. The rigorous analysis of refraction-corrected leveling data described in this paper supports the approximate computations of Strange (1981) that indicated that what was thought to be uplift at Palmdale was only the appearance of uplift created by different refraction error accumulations in successive surveys. The primary cause of this difference was reduced sight lengths starting in 1964.