Homes with shallow roof slopes that are located where heavy snow falls are vulnerable to serious damage. Heavy and wet snow creates a tremendous amount of additional weight on your roof to support. Depending on the age of your home and structural viability of the roof support, it is a good idea to try and remove the snow when you can. Removal of the snow can be dangerous, so be very careful if you are going to do this yourself. You may want to consider hiring a professional to do this for you.
Instead of getting on the roof with a shovel which is extremely dangerous, invest in a tool called a roof rake. It is a metal plate at the end of a long telescoping pole, where you can drag snow off your roof while remaining on the ground.
There is even another tool we found called the Roof Cutter from Youtube user Ken Phillips. One one side, it has two small metal rods that helps cut through the snow. Then you reverse the tool to the rake side, and the snow comes down easier.
Take a look at this great demonstration by Kent Phillips.