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Prediction circle - A circular area around the center of the typhoon at a given forecast time. Currently, the forecast circle has a 70% probability of being within the forecast circle. 12- and 24-hour forecasts are issued every 3 hours, and 48- and 72-hour forecasts are issued at 3, 9, 15, and 21 o’clock. 12-hour forecasts are sometimes omitted. 3-, 6-, 9-, 15-, 18-, and 21-hour forecasts are newly added for typhoons approaching Japan beginning April 18, 2007. The forecast circle at 3, 6, 9, 15, 18, and 21 hours is added for typhoons approaching Japan from April 18, 2007. In addition, a line connecting the center of the forecast circle is shown on the typhoon forecast map.
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