In this article, we evaluated dimensionless profiles of temperature and steam mass fraction in flows of steam and air on a flat plate by using existing data. From the heat and mass transfer equations at the condensation surface based on the gradient of temperature or steam mass fraction, we showed that the convection heat flux qconv should include the term of condensate mass flux ms, and that the dimensionless steam mass fraction Ys+ should be a function of the dimensionless distance y+, the Schmidt number Sc and the air mass fraction (1-Xs). Values obtained from the newly defined T+ and Ys+ and the existing data agreed relatively well with the linear function near the viscous sublayer, but were much smaller than the existing logarithmic law due to condensation in the turbulent boundary layer (i.e. mist generation). On the other hand, the T+ and Ys+ values obtained by using the local Nusselt number Nuy and the local Sherwood number Shy, respectively, agreed well with the logarithmic law.