Very cool interpretation of the theme. At the beginning because there's only a two weather types, I really wanted an ON/OFF switch since it makes it easier to platform smoothly and quickly which is how I tend to play my platformers. I also found the delay between when you stop the rain and the water switches direction to confusing. I kept thinking the rain would instantly stop filling up the water and perhaps there would be a short delay before the water started to go back down. That to me feels like what should happen or maybe reduce the amount of the water that keeps rising of allowing a little more collision with the water before killing me because a few time I jumped when the platform was visible and I has stopped the water but when I landed the water was still rising up a little bit or worst yet, I jumped ever so slightly too soon and died when it looked like I landed on land.
There are just "improvements" I think the game over all is unique and has great potential for some clever platforming :D