My level of boredom went to an all time high (lol), so I made a tutorial on how to make realistic thunder and an example of applying it.
NOTES:- This tutorial is targeted on beginner-amateur users of photoshop. (This means that you can follow through this tutorial even with 0% knowledge of photoshop, as long as you have the program)
- This tutorial was made on Adobe Photoshop CS3, but I'm sure the tools I used in this tutorial are available on previous versions. (Particularly version 6 and up)
Here is an application of the effect....
Before:
After:
We will only focus on making the thunder and an example of applying it, the rest will rely on your imagination.
Now let's get started!
1. Open Photoshop, click
File > New and apply these settings:
2. Once everything is set click
"OK".
3. On your keyboard press
"D" to reset the fore/back colors then on your canvas follow these intructions:
4. After applying the gradient, choose
Filter > Render > Difference Clouds.
5. So far your image should look like this:
6. Now press
"Ctrl+I" on your keyboard to invert the colors and your image should look like this:
7. After that, press
"Ctrl+L" on your keyboard then follow these intructions:
8. Once you drag the arrow to the farthest right, click
"OK". So far your image should look like this:
Congratulations! Now you have finished your basic thunder! Now I'm gonna teach you an example on how to use it....
9. Find (eg: google) a picture of a city with buildings, like this one here that I used:
10. Once you have found a nice image to put your thunder on, open the image in photoshop together with the thunder you just made.
11. After placing your thunder on the image, change the blending mode of the thunder layer to
"Screen".
Changing the blending mode of the thunder layer to
"Screen" eliminates all the black colors of that layer, so only the thunder is seen like so:
12. After that, use free transform to rotate/crop the thunder to make it look like it struck behind the buildings from the sky.
Use free transform to rotate/crop the thunder to make it look like this:
13. Once your happy with the position of the thunder, select the eraser tool and erase the bottom of the thunder to make it look like this:
14. Now lets add color to the thunder to make it look more alive, press
"Ctrl+U" on your keyboard and follow these instructions:
15. Once your happy with the color of the thunder, click
"OK".
.... And your done! Next step is to use your imagination and add some more stuff to make the thunder look more realistic, like I did here:
I greyscaled the city image, made a reflection of the thunder on the water, and added some glow on the buildings near the thunder.... but this part relies on your imagination and experience
I hope this tutorial was useful and informative especially for those who are eager to learn photoshop and also to those looking for a good effect to use on images
To see what you guys have learned from this tutorial, I'm challenging you guys to make me an image with this thunder effect applied to it. (good start would be a hand with the fingertips charging out thunder)
Tutorial by R3t4Rd 
