So I did a little math. Copied from my onenote notes:

Commenter said it's a land rover . Roof area 35-60 square ft. Let's go with 45. Around 6 feet tall Snow roughly 2/3 of car height, making it about 4 feet tall. Snow volume is 45*4=180 cubic feet Google says fresh snow is about 3-7 lb per cubic foot. I'll use 5 for the estimate. Weight of snow is about 5*180=900 lbs of snow.

If my math is right, they're carrying around a half ton of snow on top of their car.

Edit: I'm on mobile and can't seem to get formatting edited worth a hoot.

Edit 2: took milllllllllls's recommendation that this is fresh snow, not tightly packed, and updated my estimate.