Nov 03, 2011
Weather radar is getting a facelift across the country and will continue in 2012-2013. National Weather Service - Chicago just completed their upgrade to Dual Polarization technology. Dual Polarization what? In simple terms, the current nexrad radar beam transmits a radar signal horizontally to detect precipitation. Dual Polarization radiates a two dimensional beam horizontally and now vertically through the air. This new technology came in handy last night across southern Wisconsin.
A large area of moderate rainfall associated with a cold front occurred over southern Wisconsin and northeast Iowa. Colder air was able to filter in and around the Madison, Wisconsin area helping the rain mix with snow. The current nexrad radar network has a hard time determining where rain|snow lines appear on the screen. This new radar technology is able to better determine precipitation types and prove more accurate on where the rain|snow line is occurring. The cold rain did move into the Chicago area and I was able to take a couple of screenshots featuring the new products using RadarScope.
How To Use Dual Polarization - Training
It's hard to determine what is what on each of the different screenshots. However, if you would like to learn more about Dual Polarization and how to interpret the radar screen colors, below is a link to training tutorials and a video summary posted below provided by NOAA -