Radar biasa mendeteksi curah hujan berdasarkan kekuatan gelombang radio yang dipantulkan. Radar Doppler menambahkan kemampuan untuk mengukur pergerakan. Radar ini mendeteksi pergeseran frekuensi sinyal yang dipantulkan yang disebabkan oleh tetesan hujan atau kepingan salju yang bergerak, sehingga mengungkapkan apakah curah hujan sedang mendekat atau menjauh.

This velocity information shows wind patterns inside storms. Meteorologists can identify rotation that may produce tornadoes, detect strong outflow boundaries, and estimate rainfall rates more accurately. Dual-polarization upgrades further improve the discrimination between rain, hail, and non-meteorological targets.

National networks of Doppler radars provide continuous coverage over large areas. Data appear on public websites and television broadcasts within minutes. The technology has sharply reduced the average warning time for severe thunderstorms and tornadoes.

Research radars continue to refine the technique for even finer-scale measurements.