Abstract：During landfall of super typhoon Utor,Yangjiang NEXRAD products showed severe ground clutter and velocity ambiguity.This anomaly would let the weatherman make wrong judgment on the radar echo trends.Based on the radar data retrieval and combined with the data of local mesoscale automatic weather station,this paper explains the reasons for the prominent surface features and speed blur from the perspective of the radar product algorithm.Aiming at the severe ground clutter,the paper proposes to suppress the echo intensity with dynamic noise and identify ground clutter by using reflectivity vertical profiles.For velocity ambiguity,the products are made a comparison by using the fuzzy algorithm or not.The suggestions on velocity diagram application under the strong typhoon weather are presented,which is helpful to use radar products reasonably for weatherman.
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