A method determines a weather area for a motor vehicle, with which a sensor system and a communications interface are associated, which are coupled to one another via signals. The method includes: receiving data including geographical information in the form of a map; and creating a grid by dividing the received data into a plurality of adjacent grid cells. The method also includes: providing a measurement signal of the sensor system, representing a location-related local weather situation in one of the grid cells; and determining a local weather area for the respective grid cell according to the provided measurement signal.