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Storm Track for Tropical Storm Cindy

 

November 28 - December 11, 2011

The exciting dual-polarization radar upgrade to the KFFC WSR-88D will begin on November 28 and will last approximately two weeks. During this installation period, KFFC radar will be unavailable. However, neighboring radars in Columbia, SC, Charleston, SC, Robins Air Force Base, GA, Maxwell Air Force Base, AL, Birmingham, AL, Huntsville, AL and Knoxville/Tri-Cities, TN will still be operational.

This much anticipated upgrade will incorporate a new technology called dual-polarization, or dual-pol, which is part of the NWS vision to build a weather-ready nation to better protect lives and livelihoods. This new technology will provide 14 new radar products that will support our mission to serve our partners and customers in North and Central Georgia.

We strongly encourage users of our current radar information to become familiar with these new products through a series of online training modules provided by the Warning Decision Training Branch (WDTB). Modules are available for non-NWS meteorologists and non-meteorologists here.

The dual-polarization upgrade to the KJGX WSR-88D at Robins Air Force Base, GA is anticipated to begin February 27, 2012. More information on the deployment and availability of the radar data will be provided as this upgrade approaches.

What is Dual-Pol?

The current WSR-88D Doppler radars transmit and receive pulses of radio waves in a horizontal orientation. As a result, the radar only measures the horizontal dimensions of targets (e.g. cloud and precipitation droplets). Dual-polarimetric radar transmits and receives pulses in both a horizontal and vertical orientation. As a result, the returning frequencies provide measurements of the horizontal and vertical dimensions of targets, supplying forecasters with better estimates of the size, shape, and variety of targets.

 Current NWS doppler radar
 Dual-pol radar
Current NWS doppler radar Dual-polarimetric radar

Benefits of Dual-Pol
  • Improved accuracy of precipitation estimates, leading to better flash flood detection
  • Ability to discern between heavy rain, hail, snow, and sleet
  • Improved detection of non-meteorological echoes (e.g. ground clutter, chaff, anomalous propagation, birds, and tornado debris)
  • Detection of aircraft icing conditions
  • Identification of the melting layer (e.g. bright band)
Dual-Pol Products & Applications

The base radar products that have been available to users are base reflectivity, base velocity, and spectrum width. After the Dual-Pol upgrade, three new base products will be available: differential reflectivity (ZDR), correlation coefficient (CC), and specific differential phase (KDP). In addition to these three new base products, there will be several derived products. These include a melting layer (ML) product, a hydrometeor classification algorithm (HCA) product, and eight new precipitation products. Mouse-over the labels below to view examples of four of these new products. Images courtesy of the Warning Decision Training Branch.

 

Differential Reflectivity

Applications

Training & Additional Information



Radar images courtesy of WDTB
Some of the web content courtesy of NWS AMA