Will skies be clear over southern Ontario Saturday night?
Skies are likely to be cloudy over southwestern regions and mostly clear over regions near Georgian Bay and Lake Ontario during the early evening, and then become cloudy later in the evening or after midnight, due to mid-level moisture which is forecast to move eastward over southern Ontario during the evening (illustrated below for early evening).

Will skies be clear over southern Ontario Thursday night?
During the evening, mostly clear skies are expected over some regions except for regions near eastern Lake Erie and Lake Ontario, where high cloud will be visible until high-level moisture moves eastward from southern Ontario later in the night (illustrated below for late evening). During early morning, more high cloud is likely to move eastward over most of southern Ontario, caused by high-level moisture (illustrated below for early morning). Low clouds are also possible to appear over most regions overnight.

Will skies be clear over southern Ontario Wednesday night?

Mostly clear skies are expected, except for some clouds that may appear occasionally, caused by low-level moisture remaining over southern Ontario (illustrated below for late evening) following Wednesday’s cold front, as well as some high, thin jetstream-level clouds that may appear over southern regions of southern Ontario (close to Lakes Erie and Ontario) due to jetstream winds over southern Ontario overnight (illustrated below for late evening).

Will skies be clear over southern Ontario Saturday night?
Clear skies are expected, except for some high cloud over regions north of Lake Erie during early evening, until jetstream-level moisture (illustrated below for early evening) moves south from southern Ontario.

Will skies be clear over southern Ontario Friday night?
Mostly cloudy skies are expected during the evening (due to lots of low-level moisture remaining over southern Ontario), along with occasional clear breaks, and then gradually clearing skies are expected later in the night and early morning as the moisture moves southward from southern Ontario.

Will skies be clear over southern Ontario Wednesday night?

Mostly clear skies are expected during the evening, except for some low clouds that may appear occasionally, and then increasing high cloudiness is expected later in the night.

Will skies be clear over southern Ontario Tuesday night?
Partly clear skies are expected, but lots of low-level clouds, as well as some mid-level and high cloudiness will likely be visible in the moonlight, due to lots of jetstream-level moisture over southern Ontario (illustrated below for late evening).