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. See also Heatwave and Climate extreme.
IPCC
Climate Change 2022: Impacts, Adaptation and Vulnerability
IPCC Report