An update is presented of the Arcetri Atlas of water masers (Comoretto
et al. 1990). It contains the results of observations of water masers
with the Medicina 32-m antenna. The observed sources were all discove
red in the period 1989-1993, and were found either directly in the cou
rse of our own programs or were taken from the literature in which cas
e they were re-observed at Medicina. We give the observed parameters o
f 214 sources in tabular form, and present all the spectra of the 141
detections.