A simple correlation has been developed for the solubilities of solid polycyclic aromatic hydrocarbons and solid polycyclic aromatic heterocycles in pressurized hot water. The correlation is based on a first-order group contribution model of the solute activity coefficient in saturated aqueous solution (gamma(sat.)). The activity coefficient of the solute is then converted to the aqueous solubility of the solute, assuming Delta c(P) = 0. The individual group/atom contributions to In gamma(sat.) are discussed as functions of temperature. Overall, the signs and relative magnitudes of the individual contributions are consistent with what would be expected. Most group/atom contributions to In gamma(sat.) diminish in magnitude as the temperature increases, reflecting the decrease in "polarity" of water with rising temperature.