This paper examines the role played by upwelling of water and the associated reduction is mixed-layer depth in lowering sea surface temperatures during the passage of a storm. The important parameter is RU=HU/(HM+Δh). HU measures how much the wind-mixed layer is shallowed by vertical motion induced by the storm. HM is the undisturbed mixed-layer depth ahead of the storm, and Δh measures the increase in mixed-layer depth due to turbulent entrainment of water from below. Suitable quantitative definitions are given for HU and Δh, enabling RU to be calculated. With these definitions, the sea surface temperature decreases found in the three numerical experiments of Chang and Anthes (1978) are shown to be approximately a factor 1/(1-RU)2 larger than the decrease that is calculated using a one-dimensional mixed-layer model with no account taken for advection. The 1/(1-RU)2 dependence is shown to be a consequence of using the Kraus and Turner (1976) formulation for the wind-mixed layer.