Il pleut des cordes, il pleut à verse, il pleut à seaux, il pleut un déluge, il pleut la vache qui pisse, il tombe la mer et les poisons, il tombe les trombes d'eau, il pleut des clous, il pleut des grenouilles, il pleut à torrents, il pleut des hallebardes, il pleut a boire debout...

Just how many ways are there of saying it is raining cats and dogs in French- or in English for that matter?

Here it has been raining continuously for two days, the coast is flooded and the river down the road is raging.