You can ride an electric skateboard in the rain, but you're taking a risk and it will most likely damage your board.
The rain can make conditions slippery, so riding isn't as safe. Second, the board itself is not designed to be used in the rain, therefore water can enter the board and ruin the electrical elements. We do not recommend riding in the rain and advise against it. While we have made new more water-resistant battery and ESC assemblies, the board is not waterproof.