10:02 AM - 10:22 AM
[O05-03] JMA’s Information on Disaster Risk Reduction for quasi-stationary band-shaped precipitation systems
★Invited Papers
Keywords:Japan Meteorological Agency, senjo-kousuitai, heavy rainfall
In recent years, heavy rainfall caused by linear precipitation zones has resulted in serious disasters with human casualties every year, such as the heavy rains in August 2014, the heavy rains in northern Kyushu in July 2009, and the heavy rains in July 2020. Although linear precipitation events are difficult to predict, once they occur, they can cause tremendous damage. In June 2021, the Meteorological Agency began providing "Weather Information on Significant Heavy Rainfall," which uses the keyword "linear precipitation zone" to describe the situation in which extremely heavy rain is actually falling in the same area due to a linear precipitation zone, while the risk of a disaster due to heavy rainfall is rapidly increasing. This information is positioned as a supplement to the warning level equivalent information.
In order to convey the sense of danger of heavy rainfall caused by the linear precipitation zone as early as possible, on May 25, 2023, we began to use forecasting technology to announce the "Weather Information on Significant Heavy Rainfall" up to 30 minutes earlier than before. Since the start of this new operation, the announcement of information has actually been brought forward in many cases, and the dangerous situation has been communicated earlier.
In addition, from the viewpoint of encouraging evacuation behavior, it is important to call for early evacuation while it is still light, and in order for people to properly prepare for evacuation, "Calls from about half a day before heavy rainfall by linear precipitation zones" were started on June 1, 2022 in each local forecast area. In light of the current forecasting accuracy, we are announcing the information in units of local forecast districts, but in the future, we will gradually narrow down the target areas by utilizing the results of technological development, and aim to provide information in the form of distribution on a map so that the danger level can be determined in prefectural units by 2024, and then in municipal units by 2029. The Japan Meteorological Agency (JMA) urges the public to be more prepared for heavy rainfall disasters when this call is issued, as there is a high possibility that heavy rainfall will actually occur even if the criteria for issuing weather information regarding significant heavy rainfall are not met.
In order to convey the sense of danger of heavy rainfall caused by the linear precipitation zone as early as possible, on May 25, 2023, we began to use forecasting technology to announce the "Weather Information on Significant Heavy Rainfall" up to 30 minutes earlier than before. Since the start of this new operation, the announcement of information has actually been brought forward in many cases, and the dangerous situation has been communicated earlier.
In addition, from the viewpoint of encouraging evacuation behavior, it is important to call for early evacuation while it is still light, and in order for people to properly prepare for evacuation, "Calls from about half a day before heavy rainfall by linear precipitation zones" were started on June 1, 2022 in each local forecast area. In light of the current forecasting accuracy, we are announcing the information in units of local forecast districts, but in the future, we will gradually narrow down the target areas by utilizing the results of technological development, and aim to provide information in the form of distribution on a map so that the danger level can be determined in prefectural units by 2024, and then in municipal units by 2029. The Japan Meteorological Agency (JMA) urges the public to be more prepared for heavy rainfall disasters when this call is issued, as there is a high possibility that heavy rainfall will actually occur even if the criteria for issuing weather information regarding significant heavy rainfall are not met.