Science: A New Twist in Forecasting

Color-coded Doppler radar for earlier tornado warnings

Seated at a video console, the meteorologist intently watches the splashes of color as they flash across the screen. Spotting some possibly ominous patches, he zeroes in on one of the red and yellow areas. Then, fiddling with the controls, he orders up another display, showing tiny arrows circling counterclockwise and swirling ever closer in a tightening loop. After checking the coordinates on a map superimposed on his screen, the operator telephones an alert for the threatened area to the National Weather Service: a tornado may be...