Shaded asphalt in a long wet season grows moss. The moss holds moisture in the laps, granules wash off, and a tab lifts in the next wind. That sequence is the ordinary wear for Duncan and the communities around it. It is a qualitative reading of a wet, mild, east-Island valley, not a rainfall total. No millimetre figure was cited, so none is printed. Wind is part of the same reading near harbours and bays, again without a speed attached.
Read those cells as design data. They are not a promise that a given roof was built to them, and they are not a reason for this website to give engineering advice. Chemainus, Crofton, Maple Bay, Quamichan, South End, and Ladysmith do not have cells in the extract, so their pages stay silent on . Glenora and Sahtlam are names in the table whose figures were not copied into the research notes.