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A prolonged period of excessively high temperatures.
熱波の影響で農作物が被害を受けた。
Crops were damaged due to the heat wave.
Used mainly in weather reports and news articles.
Imagine a wave of heat rolling across the country.
Use 熱波 when referring to a sustained period of high temperature, not just a hot day.
Compound of 熱 (heat) + 波 (wave); originally a meteorological term.
Commonly appears in weather forecasts and news; not used for short, isolated hot days.