Weather front areas of precipitation help determine the frontal type and location. There are two different meanings used within meteorology to describe weather around a frontal zone. The term "anafront" describes boundaries which show instability, meaning air rises rapidly along and over the boundary to cause significant weather changes. A "katafront" is weaker, bringing smaller changes in temperature and moisture, as well as limited rainfall. A cold front is located at the leading edge of the temperature drop off, which in an isotherm analysis shows up as the leading edge of the isotherm gradient, and it normally lies within a sharp surface
Weather radar filter them, but scientists began to study the phenomenon. Soon after the war, surplus radars were used to detect precipitation. Since then, weather radar has evolved on its own and is now used by national weather services, research departments in universities, and in television stations' weather departments. Raw images are routinely used and specialized software can take radar data to make short term forecasts of future positions and intensities of rain, snow, hail, and other weather phenomena. Radar output is even incorporated into numerical weather prediction models to improve analyses and forecasts. During World War II, military radar operators noticed