You sent me down a rabbit hole. Holy crap! The AVERAGE rainfall in Sierra Leone in August is over 600mm... 23 inches!
I wound up finding mould on my clothes, on my fridge, inside my Jeep, etc. etc. It was extremely hard, so after a month I drove north into Mali where the rainy season was basically over :)
I saw rain staggeringly heavy more times than I can count on the West Coast of Africa - it was truly incredible. Now that I think about it, I'm not sure I ever got it on film.