Storing propane tanks outdoors is perfectly safe, but it's best to choose a spot that's away from your home. When storing your propane tanks in the winter, it's important to know that freezing temperatures aren't a problem for propane—in fact, you don’t even need to cover your tank when storing it outdoors in the winter.
Place the tank on a sturdy surface, like a piece of wood or slab of concrete, and store it uncovered or covered.
Storing propane tanks in the summer is easy, too. In warm weather your propane tank can still be stored outdoors on a flat, solid surface. You'll want to keep the tank in a shaded area so that it's not in direct sunlight for long periods of time—this will keep the tank at a safe temperature, note exceeding 120 °F (49 °C).