Why not let them to get a nice shower?(...unless they are in water retaining soil and/or there is torrential rain...)

Rainwater is absolutely better than the junk that comes out of my tap! I use a very gritty mix so I can leave them in the rain all summer long. Well, all year long, but my winters are quite dry.

They all had rain showers in the last few days and I don't use a very gritty mix. I am just careful on watering. I have a big water butt, so I try to use rainwater for my plants. It is better to be on the safe side than sorry.

I always bring my variegated Jade in out of the rain. It will get edema if I look at it too long. It's finally looking good again and we are having a huge thunderstorm so it's sheltering in the garage.

i also brought my newest less established echeverias into my dining room, or plant room, really. It's supposed to rain for 48 hours and that's way too much for them

If you know that your soil holds more water (than mine), then good for you bringing them in. You need to build a cart. It makes it easier!