Out here, if the carrier can't get to the box for any reason, then the mail won't be delivered. Whenever we have any sizeable amount of snow, this happens, since the snow plows throw enough snow in front of the box to make it impossible to pull their car up to it. So you can either shovel it out, or pick your mail up at the post office until the area is clear.

Send a notice of suspension??? - DUH! How brilliant is that?