Freezing in a one-dimensional region induced by evaporative cooling is investigated. Semi-analytic solutions in the limit of low mass transfer rates and Stefan numbers are presented. An nth order polynomial is used to express the vapor pressure function in terms of the evaporating fluid layer temperature. The freezing of a slab of calcium chloride hexahydrate subject to evaporative cooling of a thin layer of water into air is used to illustrate the utility of the model. Results show the existence of a transition region, depending upon the relative humidity and Blot number, where the fluid layer dry-out time competes with the freeze time of the slab. (C) 2001 Elsevier Science Ltd. All rights reserved.