Three inches is nothing to worry about, but if there is a heavy dumping of wet snow it can cause you problems. I usually clear my roof 3 to 4 times per year but I live in a fairly snowy climate and the weight of the snow on the roof can become substantial. I have a "roof rake" that's long enough that I can reach most of the roof from a short step ladder so it only takes about ten minutes. I have heard of a few instances of roof damage as a result of excessive snow accumulations. The owner's manual for my caravan says to remove excess quantities of snow but I know that most people never do. Use your best judgement.
------------- Ross & Brenda J.
Keswick, Ontario, Canada
N44.22283 W79.46918
Ours in in storage 20+ miles from home - there is no way we can clear the snow off it and the area that it is has had around 6 inches or so. I think a lot of people have the same situation. We have to leave it until it melts!
You might like to clear the snow around the "chimney vent " and put a plastic bag over it to stop snow etc falling down or water when it melts
------------- If you're not on a fell your wasting your feet and for 2014 it's.......Feb Castleton Mar North Yors Moors; Apr Sutton on Sea; May Thirsk; Jun Clapham/Riverside (Lakes); July Wharfedale; August Crakehall; Sept Knaresborough; Oct Wirral Park/Clitheroe