Water drop stains on upholstery?

After a heavy rain, followed by a few hot days, I went to my boat to remove the cockpit cover. There was some standing water drops on a few of the horizontal upholstered cushions, and after wiping it away, stains were left (See attached picture).

First time this has ever happened to me; almost looks like bleach stains, but definitely just from rain water that leaked through the cover. Any idea how to get rid of this? I tried 3M boat upholstery cleaner, but that didn't work.

I have not personally seen that, before, but my "guess" would be that moisture got underneath the top layer of the vinyl. Chances are, that it will go away by itself as the moisture evaporates. But you could hasten the process by leaving the cushions out in the bright sun. It may just take a few hours - or maybe a day or two. I'd at least try that, first. And then be sure to treat the vinyl on a regular basis with something like 303.

Lazy Daze said:

I have not personally seen that, before, but my "guess" would be that moisture got underneath the top layer of the vinyl. Chances are, that it will go away by itself as the moisture evaporates. But you could hasten the process by leaving the cushions out in the bright sun. It may just take a few hours - or maybe a day or two. I'd at least try that, first. And then be sure to treat the vinyl on a regular basis with something like 303.

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You were correct! Water spots disappeared after a full day in the sun. Thanks.

I would treat them with 303 like Dennis suggests. I have seen similar spots on my 185 - the rear engine cover/sunpad has some blue sections of vinyl. Have found when I keep it treated with 303 it does not happen.