Learn how to add snow to photos in Photoshop
Open the “Cottage” image.
Create a new layer (Ctrl + Shift + Alt + N) and fill it with white using the Fill tool.
Double-click on the new layer and adjust the Blend If sliders (“Blending Options”, section “Blending If:”), as shown below. This will cause the dark pixels of the bottom layer to replace the white pixels and the light pixels to be covered with white.
Add a layer mask to the snow layer (Layer> Layer Mask> Show All). Now take a round soft brush and paint over the mountains and other areas that look blurry with black.
The image already looks like everything is covered in snow. But the photo will be much better if you add snowflakes. Create a new layer and fill it with black.
Now add some noise to this layer (Filter> Noise> Add Noise).
Add some blur to the noise layer (Filter> Blur> Gaussian Blur). The degree of blur will determine the size of the snowflakes, so start small. For example, 1.2 pixels.
Now change the blending mode of this layer to “Screen”. Thanks to this, small white dots will show or hide black pixels.
Now snowflakes look so-so. They are barely noticeable and there are too many of them. To fix this, you need to add the Curves adjustment layer (Layer> New adjustment layer> Curves). Then crop the areas of the Curves adjustment layer relative to the snowflake layer by pressing Alt.
Adjust the sliders as shown below. This will hide most of the gray pixels and make the remaining pixels white.
Now there are some snowflakes in the photo. It looks good, but all the snowflakes cannot be the same size. Therefore, you need to add a few large snowflakes. How? Repeat step 5 and step 6. But when you add blur to the noise layer, use the more intense “Gaussian Blur” (try a value of 2.5 or 3).
Some large snowflakes need to be removed. Add a layer mask to the second layer where there are large snowflakes (Layer> Layer Mask> Show All. Now take a round soft brush and paint over black with most of the large snowflakes.
Add the falling snowflakes. Repeat step 5 and step 6 to create some static snowflakes.
Add a motion effect to the snowflakes you just created. Select the snowflake layer and apply the Motion Blur filter. Now, white static snowflakes will “scatter” across the screen in the direction you have selected in the Motion Blur window.
For greater realism, add snow to the roof of the cottage. Choose an almost white color (e9e8e8) and use a regular round brush to paint snow on the roof.
After that, select white and paint over the snow that you added earlier. But do not completely block it. Leave grayish areas, because the snow is not completely white.
Almost done. The photo should be winter, so add blue tones to enhance this illusion. Create a new adjustment layer “Color Balance” and add cyan and blue shades.