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low (atmospheric) pressure; low-pressure system; depression; cyclone
bad temper; foul mood; tense situation
低気圧が日本に接近中だ。
A low pressure system is approaching Japan.
低気圧が来て、雨が降っています。
A low-pressure system is coming, and it's raining.
低気圧の影響で荒れ模様だ。
Weather is rough due to low pressure.