There are occasional periods where the graph is flat, which are caused by the supplier of data being unavailable, maintenance, or other problems. The data is normally taken from the CBC web site. When it is down, so that the information it displays is more than two hours old, data is taken instead from weathernetwork.com.
A new graph shows the annual temperature cycle since 2003. Each bar shows the minimum, mean and maximum temperature for a given year and month. The graph is updated automatically each night.