Heat wave

A heat wave is a prolonged period of abnormally hot weather, typically lasting several days or longer, where temperatures rise significantly above the historical average for a particular region. During a heat wave, the combination of extreme heat and often high humidity can be dangerous to human health, causing heat exhaustion, dehydration, and even heat stroke, while also stressing power grids, agriculture, and ecosystems. Scientists measure heat waves by comparing current temperatures to long-term climate data for an area, and climate change is making these events more frequent, intense, and longer-lasting worldwide.