I was there yesterday. Friday, Oct. 2017. The vendors closed if they didnt have an enclosed tent. Some even packed up, because the rain wouldnt let up. Most of the visitors went in the food area or went to the buildings.
You bet! It takes an awful lot of serious rain and wind to get the vendors to pack up. We're talking serious storms. Most (if not all) of them will still be there in the rain; they'll just cover their tables with a tarp or plastic sheet to protect their merch IF they aren't set up indoors, OR if they don't already have an awning or canopy set up over their tables. The SMART vendors will use clear plastic sheets instead of tarps, so you can still browse their stuff without having to lift the cover. Don't forget to always bring a poncho when you go to What Cheer, just in case! And be mindful of your footwear, too. When it does rain, some areas can get a little muddy.
There are still vendors set up. They are hoping that the customers will come out in the rain.
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