Real-time Multi-Doppler Radar Analysis for Retrieving Wind Field over Dallas-Fort Worth (DFW) Metroplex

Multi-Doppler radar analysis has been widely used to retrieve three-dimensional wind fields within thunderstorms. Traditionally, high-resolution Doppler wind products are generated by post-processing, which limits its practical potential as an emergency weather warning tool. For example, tornadoes can form within a few minutes and can be relatively small and fast-moving. By using traditional weather radars (update rate: 5~6 minutes), it is very difficult to produce reliable and timely warning of wind hazards. In addition, conventional weather radars are typically deployed to provide range coverage for hundreds of kilometers and are spaced far apart. With Earth's curvature, this creates significant limitations for observations and multi-Doppler analysis in the lower troposphere, where many hazardous weather events occur. In order to improve the atmosphere sensing capability, the center for Collaborative Adaptive Sensing of the Atmosphere (CASA) has pursued a new weather radar detection paradigm termed Distributed Collaborative Adaptive Sensing, or DCAS for short, by deploying a dense network of shorter-range, low-power X-band dual-polarization radars. The DCAS paradigm produces fast coordinated scans according to the end-user needs.

Since 2012, CASA and the North Central Texas Council of Governments (NCTCOG) have initialed the efforts to create the first urban radar test bed in Dallas-Fort Worth (DFW) area. Close to the “Tornado Alley”, DFW is the largest inland metropolitan areas in the U.S., and it suffers from a wide range of natural weather hazards, including urban flash flooding, high wind and tornado. This paper presents the real-time multi-Doppler system developed for DFW Metroplex. Aiming to retrieve real-time low altitude wind information, the multi-Doppler system consists of a network of short range X-band radars and a standard S-band National Weather Service (NWS) radar. The multi-Doppler scan optimization strategy will be presented. The multi-Doppler retrieval subsystem will be described in detail. Sample observations from high wind and retrieved vector wind products will be provided.