You are using the snow effects presets from our Winter Wonderland, Let it Snow!, or ColorMade/DigiFilm Winter collections in Lightroom Classic and wish to erase some of the snow, correct?

How this works in the latest version of Lightroom Classic (with Masking Tool):

1. Click to run your snow effect preset.
2. Once the effect has rendered, select your Masking Tool
3. You should see your snow effect as a Masking Layer in the Masks Panel:
4. Click the new Mask to expand and view your options for that mask (you should see a brush effect selected when you do this underneath the mask):
5. Select "Erase" in your brush panel to the right and erase the parts of the snow effect you'd like to remove (like over faces):
   

How this works in earlier versions of Lightroom Classic:

1. Click to run your snow effect preset.
2. Once the effect has rendered, select your Local Adjustment Brush
3. With the local adjustment brush selected, click on the little gray pin on your image (this controls the snow effect)
4. With that pin selected your brush panel settings should look like so:
   
5. You will select Erase as seen above to erase the parts of the effect you would like to remove.