Chapter 11 is an assessment of extreme phenomena, encompassing weather and climate timescales as well as compound events. These include heat waves, cold snaps, heavy precipitation, droughts, tropical cyclones and other severe storms. Limitations of observations and models including model evaluation of these phenomena are addressed. Recent advances in understanding the mechanisms, drivers and feedbacks leading to extremes are discussed. Attribution of changes in these extremes including individual extreme events are presented. Projected changes in extreme weather properties as well as potential surprises are assessed.