Last edited 01 May 2025

Extreme weather event

AR5 Climate Change 2014: Impacts, Adaptation, and Vulnerability, Glossary, published by the Intergovernmental Panel on Climate Change (IPCC) suggests that: ‘An extreme weather event is an event that is rare at a particular place and time of year. Definitions of rare vary, but an extreme weather event would normally be as rare as or rarer than the 10th or 90th percentile of a probability density function estimated from observations. By definition, the characteristics of what is called extreme weather may vary from place to place in an absolute sense. When a pattern of extreme weather persists for some time, such as a season, it may be classed as an extreme climate event, especially if it yields an average or total that is itself extreme (e.g., drought or heavy rainfall over a season).’

Climate Change 2021 – The Physical Science Basis, Annex VII: Glossary, written by the Intergovernmental Panel on Climate Change (IPCC) and published by Cambridge University Press in 2023, defines an extreme/heavy precipitation event as: ‘…an event that is of very high magnitude with a very rare occurrence at a particular place. Types of extreme precipitation may vary depending on its duration (hourly, daily or multi-days (e.g., 5 days)) though all of them qualitatively represent high magnitude. The intensity of such events may be defined with a block maxima approach such as annual maxima or with a peaks over threshold approach, such as rainfall above the 95th or 99th percentile at a particular place.’

See also: Extreme sea level and Extreme weather.

[edit] Related articles on Designing Buildings

Designing Buildings Anywhere

Get the Firefox add-on to access 20,000 definitions direct from any website

Find out more Accept cookies and
don't show me this again