An update is presented of the Arcetri Atlas of water masers (Comoretto et al. 1990A&AS...84..179C). It contains the results of observations of water masers with the Medicina 32-m antenna. The observed sources were all discovered in the period 1989-1993, and were found either directly in the course of our own programs or were taken from the literature in which case they were re-observed at Medicina. We give the observed parameters of 214 sources in tabular form, and present all the spectra of the 141 detections.