To solve a problem that sufficient forecasting precision is not provided because only horizontal distribution information as to planar reflection intensity is processed as a time-serial image data concerned in a meteorological condition in a conventional meteorological radar system.

This radar system is provided with a space observation part 1, an observation data warehouse part 2 for accumulating observed data, a condition extracting part 3 for calculating the observed data discretely in a three-dimensional space, a time-serial database 4 for accumulating the observed data time-serially, a state transition analyzing part 5 for preparing a three- dimensional variation forecasting model, a state transition database 6 for accumulating the variation forecasting models and the like and a meteorological condition displaying part 7.