This article describes the Japan Meteorological Agency (JMA) severe weather terminology. The JMA defines precise meanings for nearly all its weather terms as the Information for Severe Weather Preparation (防災気象情報, Bousai Kishō Jōhō). This article describes JMA terminology and related JMA weather scales. Some terms may be specific to certain regions.
Severe weather bulletins are issued as an advisory or a warning, depending on the risk or severity of the event. Less severe events that could be a cause for concern will be issued as a bulletin or an advisory.
Weather advisories and warnings are issued when potentially hazardous weather is occurring or is forecast for the short-term period.
Due to its local-scale nature, an advisory is typically issued in advance for public forecast areas where conditions may be favorable for the development of severe weather. A warning is issued for areas where severe weather is imminent or occurring.