Raw temperature files from the Milos shallow water hydrothermal fields acquired in Paleochori Bay, Summer 2019 (23-27 Sep 2019). Files are separated in two folders : "Hexagon" study site  in Paleochori Bay, and "Paleochori_Bay" for the remaining  of the sites. Records are given by temperature sensor type  (NKE, ThermalBlanket, WHOI_HighT), and include  time-stamps (UTC time) and the temperature reading (in °C), in text or csv files. The Hexagon was studied during 2019 Milos Fieldwork in  dives 1, 2 and 3 using NKE and WHOI_HighT sensors along  with a thermal blanket. Paleochori Bay was studied during dives 4, 5 and 6  using NKE sensors only. Table S1 and S2 provide details of all the deployments,  and of the temperature values reported in the paper.  These tables also provide the start and end time for  each deployment, as well as the corresponding instrument.