We don't recommend washing and then wrapping in foil immediately. If you plan on baking on the BBQ grill the next weekend, we recommend storing the potatoes in a cool environment with plenty of ventilation so they can dry out. This is much better than washing, wrapping in foil and having the potato, which is a living organism, perspire or get moldy or suffer from infection. Especially important, if the potato has external cuts or bruises, to not seal up a wet potato in foil for any extended amount of time. We recommend washing the potato under a faucet, using a vegetable brush to clean any dirt accumulated in the eyes. Then placing on a rack or colander with holes to allow some air circulation before placing in refrigeration till you are ready to bake the potato.