A washing machine automatically executing steps of wash, rinse and dehydration includes a temperature sensor sensing the temperature of water contained in a rotatable tub so that a washing operation can be performed in accordance with the water temperature and the atmospheric temperature. The wash step control data including a wash period and intensity of the water stream is determined based on the water temperature sensed by the temperature sensor during the wash step. The dehydration step control data including a dehydrating period or the rotational speed of the tub is determined based on the water temperature sensed by the temperature sensor during the rinse step.