The other usage of -Dİr conveys the sense of making an estimation or
it is used when talking about highly probable events. You can usually understand
which -Dİr is being used by context and intonation
but since these are hard to imply in written format, there'll be an explanation in the note section for each item.
Let's see some examples of the guess usage:
-Kanada'da hava nasıl?
-How's the weather in Canada?
+It's probably cold./It must be cold.
|İşten eve 50 kilometre vardır.
||From work to home is probably about 50 kilometers.
|Bu saatte çok trafik vardır, gitmeyin.
||There's probably a lot of congestion at this hour, don't go.