The Weather Orb is able to change the weather. You right click with it in hand and a the screen on the right appears. When in the menu you have a choice of making the weather hazy, clear, rainy or stormy. When clicking "Credits" It comes up with a screen that says (Assuming it says.) The name of the mod creator for the Weather Orb who is "aidancbrady" in the "Mekanism" mod. The weather orb is obtained from the Theoretical Elementizer.
Weather Orb -- A strange ball of an unknown material that can change the weather at your desire.