Ball rotation

[BretMan]

While the normal ball rotation procedure is pretty simple, today I was wondering about this one...

If you're working a game with light rain, a muddy field or dew in the grass, quite often someone will have a towel handy to dry balls. In these conditions, the chances of a pitcher asking for another ball during an inning are much greater because the one she has is wet or muddy.

In this case, do you...take the ball she has and get it wiped down, then give her back the same ball (as to maintain the ball rotation procedure)? Allow a dry(er) ball to be put into the game or pull on from your bag? Tell her, "Too bad", because the ball rotation procedure says she has to continue pitching with the ball she has? Some combination of the above?

I guess what I'm asking is if the ball rotation procedure can be ignored, at the umpire's discretion, if he thinks that weather conditions warrant.