Too cold to venture outside with your camera? If you have Photoshop (CS, CC, Elements), here’s some fun things you can do with the images you already have.
And don’t forget Monochrome – sometimes removing colour from an image actually makes it more appealing (or tells the story more succinctly):
Of course, if the sky is covered with snow filled clouds, the scene is pretty well monochromatic already. These two images might make a better example.