[cbr]

    I am not sure I understand where you took
    your numbers from.

The links I listed give 3,016 homeless people for Montreal and 6,686 for SF. Dividing by their populations, you get the per-capita rates I gave.

    I believe it is HIGHLY incorrect to compare the
    number of homeless people from cities located in
    DIFFERENT countries.

Yes, I'm sure country has an effect, and we can't count the entire SF vs Montreal difference as being due to weather. Similarly, different cities have different institutions and are otherwise, so figuring out the effect of weather is pretty hard.