Wear a hat.
I believe performances happen rain or shine, so dress accordingly - hat, rain coat. Just call/email and ask. If you need to leave a message, someone will get back to you.
If you think it will rain, bring an umbrella. The crowd will be pretty thin, so you can generally use your Bumbershoot without blocking anyone. And the cast works extra hard to make sure the show is just as strong because we really appreciate every audience member willing to sit through that :)
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