https://www.britannica.com/place/Pacific-Ocean/Temperature-and-salinityTides and currents plus the waves caused by the typhoon would keep everything well mixed up and moving around. In perspective itd be like taking a 100 gallon tank filled with saltwater and pouring in 10 ml of freshwater. Not going to make a difference :)
https://www.int-res.com/articles/meps/181/m181p309.pdf
