Some images would really benefit with falling snow, but if you missed out you could always add it later with Photoshop. That way you can keep warm and dry!
First we need to create a new empty layer by clicking on the Create new Layer Icon shown above. Now with the foreground colour set to white select the Paint Bucket Tool (short cut K) and fill the new layer with white. You can also use Edit > Fill to turn the layer white.
Working on our new layer we now need to add Noise this can be found under Filter > Noise >Add Noise. Set the amount to around 145 and click both the Gaussian and Monochromatic boxes. To give the impression of falling snow we select Motion Blur - Filter > Blur > Motion Blur and set the Angle to about 85 and the pixels to 11 approximately. This is now starting to look more like a blizzard!
Using the Brightness /Contrast found under the Image > Adjust > Brightness / Contrast menu set the Contrast to +100 and the Brightness to approximately -15. Now from the Filter menu select Filter > Blur > Gaussian Blur and enter Radius of 1.5, this will soften the snow but try experimenting with this value.
Finally on the Layers palette select Lighten from the blend mode - then wrap up warm!! :-)
