This paper debates the 'temperatures' of the chief Baltic ethnic groups: Estonians, Latvians, Lithuanians, their three Russian-speaking communities, and the Latgalian and Polish minority groups in Latvia and Lithuania, respectively. It attempts to make the ethnic temperature concept quantitatively rateable, while preserving the chance for an ample qualitative description to grasp its nature. Each ethnic group consists of widely differing subgroups with their own distinct ethnic temperature. The subgroups' (ingroup) interaction affects both the mean temperature of the in-group and the temperatures of important out-groups.