I ski in my yard about every day and this happens about 3/4 of the time that it's below freezing. The way I get the snow off is to hit it off using my bindings. First if there's snow in the binding itself I poke it out with my poles. Then to get it off my boots, I hit the heel part of the boot on the toe piece of the binding. I only pull back, I always seem to miss when I push it forwards. For the toe part of the boot, I go both ways and I can seem to get it off the boot. Not sure if this is the exact problem you're talking about but if what I mentioned comes up, that's how I solve it.