ADDING SNOW/RAIN
Open the car you want to add snow to.
Create a new layer. Fill it with black, now go to filter>noise>add noise. Amount = 70, gaussian and monochromatic. Next, go to filter>blur>gaussian blur. Radius = 1.5 pixels
Now, go to image>adjustments>levels (or press control + L)
Channel = rgb Input levels = 90, 1.00, 120 Output levels = 0, 255
Set the 'snow' layer's blending mode to 'screen' (this is done on the small layers box in the bottom right hand corner).
If you want it to be more intense, then duplicate the layer again
If you want it to be a bit rainy, then go to Filter>Blur>Motion Blur. On that menu, you can adjust the angle and speed of rain.
