Abstract: Apparatus and related methods are provided for automatically recalibrating a SAW scale for changing environmental factors. During a period of time when there is no change to a weight applied to the scale, readings of SAW transducers which relate to weight indications and environmental factor indications are taken for two adjacent operating modes of the scale, and two calibrated weight calculations are made utilizing those readings. The difference in calibrated weight calculations is then related to a variable utilized to transform the readings into weights, which is updated, thereby recalibrating the scale.