Linear rainbands. Once they occur, the area is hit with heavy downpour for an extended period of time, resulting in flood damage. In Japan, this phenomenon has been drawing attention ever since it struck in 2014, bringing torrential rainfall to Hiroshima Prefecture. While various studies led by the Japan Meteorological Agency are underway, it is still difficult to make accurate forecasts of linear rainbands at this point. When and where do linear rainbands occur? The mechanisms are still not understood. Find out how researchers are taking on the challenge to predict linear rainbands by accurately observing the location and the amount of water vapor in the atmosphere and performing rapid calculations.