At 6th level, the storm grants you benefits even when your aura isn't active. The benefits are based on the environment you chose for your Storm Aura.
Desert
You gain resistance to fire damage, and you don't suffer the effects of extreme heat, as described in the Dungeon Master's Guide. Moreover, as an action, you can touch a flammable object that isn't being worn or carried by anyone else and set it on fire.
Sea
You gain resistance to lightning damage, and you can breathe underwater. You also gain a swimming speed of 30 feet.
Tundra
You gain resistance to cold damage, and you don't suffer the effects of extreme cold, as described in the Dungeon Master's Guide. Moreover, as an action, you can touch water and turn a 5-foot cube of it into ice, which melts after 1 minute. This action fails if a creature is in the cube.