NWS will begin to roll out dual polarization for all Nexrad's starting this year and finishing in 2012. Local radars will be down for up to 2 weeks; no mention when HGX will get their upgrade. Duo pol will provide-
- Better rainfall estimation
- Severe weather signatures
- Tornadic debris detection
But wait, there's more-
http://www.norman.noaa.gov/nsww/wp-cont ... WW2010.pdf