In this project we approximate the water-containing, semi-permeable, canvas bag (known as a Lister bag) as a “lumped capacitance” and use standard forced convection correlations for a cylinder in crossflow to find the sensible and latent heat transfer (the latter associated with evaporation from the outer surface to the bag). With this information we predict the temperature-time history of the water as a function of atmospheric conditions including wind speed, air temperature and relative humidity. This project makes extensive use of the air-water property spreadsheet in HTT.