While Ottawa won't get as much rain out of this system as southern Ontario, the weather is going to be miserable over the next couple days.
Next week won't be much better. A weak clipper will bring light rain Monday. A southern branch storm will bring the possibility of rain Thursday. However the bigger story is the trough and colder air that will come in behind this second system. This will set up the coldest period so far of this fall with snow showers likely, even potentially LES for next Friday and Saturday.