Heat wave
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A heat wave or heatwave, sometimes described as extreme heat, is a period of abnormally hot weather that lasts for multiple days. A heat wave is usually measured relative to the usual climate in the a
A high pressure system in the upper atmosphere traps heat near the ground, forming a heat wave (for North America in this example)
Scorched grass in Greenwich Park, London, England, during a heatwave in August 2022.
Heat stroke treatment at Baton Rouge during the 2016 Louisiana floods
The National Weather Service risk categories for NWS HeatRisk
Extreme weather
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Extreme weather includes unexpected, unusual, severe, or unseasonal weather; weather at the extremes of the historical distribution—the range that has been seen in the past. Extreme events are based o
A tornado is an example of an extreme weather event.
2003 European heat wave
Cold wave in continental North America from Dec. 3–10, 2013. Red color means above mean temperature; blue represents below normal temperature.
A California reservoir in 2015 with low water levels due to drought conditions. From 2011 to 2017, California experienced one of its driest periods in recorded history.