NWS Doppler radar produces 1-hour, 3-hour, user-defined, and storm-total precipitation estimates. Although limitations exist, the overall estimates usually are quite good and alert forecasters to locations where heavy precipitation is or has occurred. This is very important, for example, during thunderstorm events where forecasters need to assess flash flood potential as necessary. Dual-pol now also produces precipitation estimates based on various new algorithms.
At left is a storm total precipitation estimate on May 20, 2005 that showed a band of heavy convective rainfall across southwest Indiana and central Kentucky. Estimated amounts of 2.5-5 inches (yellow shades) were noted with up to 6 inches (red) over Grayson County. Other heavy rainfall occurred over south-central Kentucky. The data can be animated to see where accumulation is most rapid.