Abstract: An energy-efficient, miniature, hot sensor anemometer designed for battery operation, including an hot airflow sensor, exposed omnidirectionally to the ambient air, for measuring speed of airflow. The anemometer is a subsystem incorporated in a miniature, self-contained environmental monitor. The sensor's electrical resistance changes in relation to the sensor's temperature, and is a function of the ambient air temperature and the speed of airflow to which said sensor is exposed. The anemometer operates in a cyclic mode such that said sensor is preheated, by passing electrical current pulses through it, to a first temperature value above the ambient air temperature, the electrical current flow through said sensor is then terminated, and the sensor, exposed to the airflow, is allowed to cool. The electrical resistance of the sensor changes in response to the cooling of the sensor through convection transfer of its heat to the moving air molecules.