Technicians monitor the output from the S-Pol radar inside an accompanying trailer. The S-Pol radar is a portable Doppler radar developed at the National Center for Atmospheric Research for use by NCAR and university scientists. S-Pol is a polarimetric radar--its polarized signals gather information in vertical and horizontal orientations, which allows rain and hail to be distinguished from each other. S-Pol can be packed into a group of trailer-like containers and shipped worldwide for deployments in remote and difficult sites.