The noun 暴雨 (bàoyǔ) means 'rainstorm,' 'torrential rain,' or 'downpour.' It describes extremely heavy rainfall. For example, 今天下午有暴雨 means 'There will be a rainstorm this afternoon.' Weather warnings often use the term 暴雨预警 (rainstorm warning).
气象台发布了暴雨红色预警。
Qìxiàngtái fābù le bàoyǔ hóngsè yùjǐng.
The meteorological station issued a red rainstorm warning.
昨天的暴雨导致好几条路被淹了。
Zuótiān de bàoyǔ dǎozhì hǎo jǐ tiáo lù bèi yān le.
Yesterday's heavy rain caused several roads to be flooded.
出门记得带伞,下午可能有暴雨。
Chūmén jìde dài sǎn, xiàwǔ kěnéng yǒu bàoyǔ.
Remember to bring an umbrella when you go out; there might be a heavy rainstorm this afternoon.