How Often do you let the ball roate during bad weather?

In the Pacific Northwest there are fields with good enough drainage that it can rain for hours before the fields really become unplayable.

I had a game a couple of weeks ago that the rain had started about 20 minutes prior to game time.

With the Ball being so wet both pitchers were having problems controlling their pitches.

In this situation how often do you let the pitcher request the somewhat dryer ball in your ball-bag.

No. In this situation I use the defensive dugout as a virtual ball-bag. Coach has a towel and will dry the ball coming out of play. Coach throws the dry ball to me, I confirm it is a valid game ball and hand it to the catcher. I allow F1 or F2 to request a dry ball at any time, and I will have balls fielded off the grass routinely just tossed to the dugout for a new ball (I always handle the ball on the way in.)

Not exactly kosher, but practical. And the players execute it without unreaonable delay.

Last weekend it started to rain a bit after 1st inn., the outfield was already wet by rain earlier. I've changed balls after every hit. Once a ball had been on the ground, it went into the "home dug out". People there were very busy with towels.
The game took more time by this, but the girls wanted to play. It was competition-opening for them.

One time I had to send a runner back. I was inconsequent with calling "time", 'cause I was under impression that the runners would see that the ball beïng changed meens play dead... Wrong! My mistake, but coach didn't make a big thing out of it. After that one incident, I called "Time" every time...

Really whenever they ask. I will allow them to throw it to their bench and have the bench keep 'em dry. I will allow them to swap balls that way unless I see something "fishy" going on. I have never had a problem with someone trying to slip a "doctored ball" in. I also try and address that at the pre-game.

I use the basecoaches instead of the pitcher's dugout. They are SURE not to deface the ball "on accident". I too will let pitcher swap out a ball at any time during a situation like this.

Often, whenever, and I carry extra balls in wet games. I check them myself, especially if they go to the outfield.