In fact, this picture is inspired by the production of lightning effect, if you know some of the lightning before the production method, I believe it will be easier to do.
This example mainly uses the Photoshop cloud filter, the layered cloud filter, the layer effect, the color adjustment and so on.
Final effect Diagram
[First step] open Photoshop, create a new file, transparent background, set a good size.
[Step two] draw a positive circle with the selection rectangle tool on the layer (hold down shift) and switch to the channel panel to save to Alpha 1.
[Step three] back to layer tool surface, filter-render-cloud; filter-render-layered clouds. Then a layer is copied, the two base layers one to make the ocean sky, and the other to make the terrain.
[Step Fourth] Select a base layer, call menu image-Adjust-auto contrast, image-adjustment-automatic levels, image-adjust-tonal homogenization, image-adjust-reverse, image-adjust-color balance; adjust to sky-blue, if not once, then try two more times, adjust to their more satisfactory results.Classification: