A baffle for disposition in a sump having a fluid containing cavity is disclosed. A first portion of the baffle has an outside edge abutting a side wall of the sump and an inner edge defining an opening. A second portion of the baffle extends downwardly from the inner edge to a lower edge abutting a bottom wall of the sump. At least one jalousie divider is disposed along the second portion of the baffle to regulate fluid flow through the baffle based on fluid temperature. A controller is coupled to the jalousie divider to selectively drive the jalousie divider to a closed position that prevents fluid flow through the baffle when the fluid temperature is below a temperature threshold and an open position that permits fluid flow through the second portion of the baffle when the fluid temperature is above the temperature threshold.