Alarm level

From Glossary of Meteorology



alarm level

Likelihood of or confidence in a forecast or report of dangerous, threatening, or damaging weather-related phenomena.

For example, a warning or watch may be issued based on either a forecast or observation of severe thunderstorms, flash flooding, river flooding, high winds, winter storms, etc. The National Weather Service does not wait for the event to occur before warning the public; there must be some lead time associated with it, such as a flood warning prior to reaching flood stage.


Copyright 2022 American Meteorological Society (AMS). For permission to reuse any portion of this work, please contact permissions@ametsoc.org. Any use of material in this work that is determined to be “fair use” under Section 107 of the U.S. Copyright Act (17 U.S. Code § 107) or that satisfies the conditions specified in Section 108 of the U.S.Copyright Act (17 USC § 108) does not require AMS’s permission. Republication, systematic reproduction, posting in electronic form, such as on a website or in a searchable database, or other uses of this material, except as exempted by the above statement, require written permission or a license from AMS. Additional details are provided in the AMS Copyright Policy statement.