Are car covers for leaving your car semi-outdoor any good?

This may be a dumb question but recently I bought a new car that I am basically driving almost every day and the thing is I live in a really humid country where it rains basically almost every day and whenever I wash my car, it just rains a few hours later or overnight and since the awnings in my house covers the car up till the hood, I always get watermarks on the hood of my car and it gets super annoying and its so obvious because it’s black. So I thought that maybe if I cover my car it could potentially avoid these watermarks from forming. I may also be moving to another place temporarily and only be able to come back occasionally on weekends and as of now I might not be bringing the car thus leaving the car at my house which may leave the car exposed to constant rain and sunlight on the hood area only which im afraid may damage the paint or the coating overtime. What do you guys think?