1. A method comprising: a computer system receiving image data of a field comprising a plurality of pixels, precipitation data for the plurality of pixels of the image data of the field indicating one or more amounts of rainfall over one or more regions of the field, elevation data indicating one or more elevations over the one or more regions of the field, and soil property data indicating one or more properties of soil found across the one or more regions of the field; the computer system running a flow simulation over the plurality of pixels of the image data of the field, and based on the precipitation data for the plurality of pixels, the elevation data, and the soil property data, to identify a set of pixels, of the plurality of pixels within the image data, that are likely to have ponding water after the rainfall; for each pixel, from the set of pixels within the plurality of pixels, the computer system: estimating, using a classifier trained to estimate probabilities that pixels represent ponding water, a probability that a pixel from the set of pixels represents water; assigning the probability to the pixel; determining, based on the probability assigned to the pixel and particular precipitation data, from the precipitation data, assigned to the pixel, a class, from one or more classes, to indicate the probability that the pixel represents ponding water after the rainfall; the computer system generating one or more alerts corresponding to the one or more classes determined for the set of pixels.