Abstract: A method and apparatus for determining the predictability of an element in a weather radar image. An image filter approximating the envelope of the organized storm radar image is applied to a pixel in a received weather radar image to generate a processed pixel value. A variability value is determined from the variation in the pixel values of the neighboring pixels which lie within the image filter. The predictability is generated from the processed pixel value and the variability. Pixels having high processed pixel values and low variabilities typically correspond to pixels within a strong organized storm and, therefore, are more predictable. Pixels having low processed pixel values and high variabilities, such as pixels representative of airmass storms, generally have lower predictabilities.