A windshield wiper control, e.g. for use in automobiles, receives information as to the amount of humidity on the windshield from a sensor (1) which is arranged within the area which is swept by the windshield wipers, and adjust the wiper frequency in relation thereto. The windshield wiper control includes a circuit (2) which remembers the signal from the sensor just after the windshield wiper has passed the sensor. The signal is compared to the signal directly from the sensor by a comparator (3). Having detected a certain change, the amplifier (4) is activated which turns on the wiper motor through a relay (5). The sensor may be of the capacitive type.