reporter: current radar uses horizontal beams to sweep storm clouds. dual polar radar sweeps with horizontal and vertital themes, sending enhanced images. absent of spot spotter reports from the ground there that site, especially at night or in rural areas, to be able to see that possible debris ball or signature from a tornado on the ground gives forecasters increased confidence. reporter: confidence to trigger alerts sooner with warning information that is more direct. so instead of saying, severe thunderstorm capable of producing a tornado, we can say a tornado is on the ground, moving this direction. reporter: how are the upgrades coming? there are 161 sites across the u.s. 50 have been upgraded. it will take another year to get everybody set. tell cost the taxpayers $50 million, but forecasters say it will be saving a lot of lives. gregg: thank you very much. heather: could the massacre of afghan civiliance, allegedly at the hands of a u.s. soldier