A method of controlling a mobile work machine (102;200), the method comprising: receiving an image of spectral response at an area of terrain corresponding to a path of the mobile work machine; generating an image distance metric based on a distance between the spectral response and a base spectral response model corresponding to the terrain; comparing the image distance metric to a distance threshold; and controlling a controllable subsystem of the mobile work machine based on the comparison, wherein the base spectral response model comprises a base color vector, and generating the image distance metric comprises determining an image color vector for the received image and determining a distance between the image color vector and the base color vector; characterized by the steps of generating a precipitation factor based on historical precipitation data corresponding to the terrain, and generating the image distance metric based on the determined distance between the image color vector and the base color vector, and the precipitation factor, wherein a higher value of the precipitation factor indicates a higher possibility of standing water or mud and increases the image distance metric for subsequent threshold comparison, and/or by the steps of generating a terrain elevation factor based on terrain elevation data corresponding to the terrain, and generating the image distance metric based on the determined distance between the image color vector and the base color vector, and the terrain elevation factor, wherein a smaller elevation factor indicates that the elevation of the coordinates of the image is relatively higher compared to the average elevation of the surrounding terrain and that there is a smaller possibility of standing water as the portion of the terrain is higher relative to the surrounding terrain and the image distance metric for subsequent threshold comparison is lowered, wherein the terrain comprises a field and the mobile work machine comprises an agricultural machine configured to perform an agricultural operation on the field. receiving an image of spectral response at an area of terrain corresponding to a path of the mobile work machine; generating an image distance metric based on a distance between the spectral response and a base spectral response model corresponding to the terrain; comparing the image distance metric to a distance threshold; and controlling a controllable subsystem of the mobile work machine based on the comparison, wherein the base spectral response model comprises a base color vector, and generating the image distance metric comprises determining an image color vector for the received image and determining a distance between the image color vector and the base color vector; characterized by the steps of generating a precipitation factor based on historical precipitation data corresponding to the terrain, and generating the image distance metric based on the determined distance between the image color vector and the base color vector, and the precipitation factor, wherein a higher value of the precipitation factor indicates a higher possibility of standing water or mud and increases the image distance metric for subsequent threshold comparison, and/or by the steps of generating a terrain elevation factor based on terrain elevation data corresponding to the terrain, and generating the image distance metric based on the determined distance between the image color vector and the base color vector, and the terrain elevation factor, wherein a smaller elevation factor indicates that the elevation of the coordinates of the image is relatively higher compared to the average elevation of the surrounding terrain and that there is a smaller possibility of standing water as the portion of the terrain is higher relative to the surrounding terrain and the image distance metric for subsequent threshold comparison is lowered, wherein the terrain comprises a field and the mobile work machine comprises an agricultural machine configured to perform an agricultural operation on the field.