A method performed by a radar system on an aircraft, the method comprising: initializing normalized radar cross section values for ground elements and reflectivity values for weather elements; initializing uncertainty parameters of normalized radar cross section for the ground elements based on a type of ground associated with each of the ground elements; initializing reflectivity uncertainty parameters for the weather elements, wherein initializing reflectivity uncertainty parameters for the weather elements comprises initializing of weather uncertainty parameters based on a priori information, wherein the a priori information comprises uplinked weather data from a ground-based radar; receiving a radar measurement from the radar system as a result of a radar return from a transmitted radar beam; generating a prediction of a radar measurement based on an element value multiplied by a weight factor, wherein the weight factor is based on a location of the element value within the transmitted radar beam, and wherein the element value is determined by a sum of the values of the ground and weather elements that define a measurement of the element value; subtracting the generated prediction of the radar measurement from the received radar measurement; adjusting one or more of the reflectivity values based on a result of the subtraction multiplied by a filter gain, wherein the filter gain is based at least in part on at least one of an uncertainty parameter from the initialized uncertainty parameters of normalized radar cross section for the ground elements or an uncertainty parameter from the initialized reflectivity uncertainty parameters for the weather elements; and storing the one or more adjusted reflectivity values, wherein the stored reflectivity values represent a portion of environment around the radar system. initializing normalized radar cross section values for ground elements and reflectivity values for weather elements; initializing uncertainty parameters of normalized radar cross section for the ground elements based on a type of ground associated with each of the ground elements; initializing reflectivity uncertainty parameters for the weather elements, wherein initializing reflectivity uncertainty parameters for the weather elements comprises initializing of weather uncertainty parameters based on a priori information, wherein the a priori information comprises uplinked weather data from a ground-based radar; receiving a radar measurement from the radar system as a result of a radar return from a transmitted radar beam; generating a prediction of a radar measurement based on an element value multiplied by a weight factor, wherein the weight factor is based on a location of the element value within the transmitted radar beam, and wherein the element value is determined by a sum of the values of the ground and weather elements that define a measurement of the element value; subtracting the generated prediction of the radar measurement from the received radar measurement; adjusting one or more of the reflectivity values based on a result of the subtraction multiplied by a filter gain, wherein the filter gain is based at least in part on at least one of an uncertainty parameter from the initialized uncertainty parameters of normalized radar cross section for the ground elements or an uncertainty parameter from the initialized reflectivity uncertainty parameters for the weather elements; and storing the one or more adjusted reflectivity values, wherein the stored reflectivity values represent a portion of environment around the radar system.