Originally Posted by
GriddleCakes
But if you ride in deep enough snow, you'll pack the rear cassette with snow eventually, which might be what's happening. If the chain is still grabbing the chainrings, then the problem is at the back of the drivetrain, and it's a pretty common one for snow cyclists.
When riding in deep enough snow to be kicked up into the cassette, I just pick a gear and stay there; as long as the chain doesn't change cogs then the cog you're on will stay usable and the chain won't skip.
That's the only problem remotely like this that has ever happened to me. It doesn't happen often, no more than twice a winter on average. It's dependent on the temperature and snow conditions, so you might hit a stretch when it does happen more often.
A courier used to keep a can of WD 40 and spray the chain and cassette to help with the problem.
I usually only lose a couple of gears with it, so it will slow me down or make things more difficult. But on the other hand, my whole life is like that and I'm used to it.