a heavy fall of rain that often starts suddenlyWordfinderraindownpour,drought,flash flood,monsoon,precipitation,puddle,rain,shelter,shower,squallOxford Collocations Dictionaryadjectiveheavy,torrential,relentless,…prepositionin downpourphrasesa downpour of rainSeefull entrySee related entries:RainExtra examplesWe got caught in a torrential downpour.For the past six hours the downpour had been continuous and torrential.The suddenness of the downpour had caught the three of them by surprise.
See downpour in the Oxford Advanced American Dictionary