Will skies be clear Saturday evening over southern Ontario?
It looks like partly cloudy skies due to various amounts of mid-level cloudiness that will be moving northeastward across southern Ontario overnight. The images below show forecast charts for mid-level moisture at UTC 03:00 (22:00 EST) and UTC 06:00 (01:00 EST) and these charts indicate that increasing cloudiness can be expected during the evening, especially over southern regions of southern Ontario while regions closer to Georgian Bay may see less cloudiness than southern regions.

 

Will skies be clear over southern Ontario Friday evening?

It looks like gradually clearing skies near the Toronto region, clear skies earlier over southwestern regions west of Toronto, and cloudiness taking longer to clear over the regions east of Toronto, as moisture moves eastward from southern Ontario following Friday’s cold frontal zone. Lake effect cloudiness shouldn’t be significant over southwestern regions with Lakes Huron and Erie mostly ice-covered. 

The chart below shows the mid-level moisture (700 hPa level) moving eastward from the Toronto-to-Georgian Bay area during the evening.

Will skies be clear Wednesday night over southern Ontario?

It looks like very clear skies are likely during the evening, and generally clear skies from approximately sunset until morning twilight. After midnight, high cloudiness is likely to appear, especially west of the Toronto area, due to high and mid-level moisture ahead of a warm front.

With the moon not rising until about 4 hours after sunset, skies are likely to be clear and dark during the early evening. Later, as winds diminish, fog may develop especially in lower-elevation locations. The forecast charts below (if they load onto the blog site correctly) show the very dry air at mid-levels (700 hPa level) that will result in clear skies during the evening, and the moisture at jetstream levels (250 hPa level) during the early morning that may result in some visible high-level cloudiness over southwestern Ontario after midnight and before dawn.

Will skies be clear over southern Ontario Sunday night?
It looks like very clear skies are likely after some clouds (associated with a mid-level trough and weak low pressure disturbance) move eastward from southern Ontario during Sunday afternoon and diminish (and probably disappear) by around sunset. A strong high pressure ridge is forecast to move eastward over southern Ontario overnight. Dry air and subsidence ahead of the ridge will be causing clear skies over southern Ontario.

Will skies be clear over southern Ontario Saturday evening?
It looks like mostly clear skies are likely, except for some low clouds during the early evening, followed by increasing mid-level cloudiness after midnight and before dawn.
The chart below shows increasing moisture (700 hPa level) that will be available to form mid-level cloudiness, moving southeastward over southern Ontario at UTC 06:00 (EST 01:00) early Sunday morning.

Will skies be clear over southern Ontario Tuesday evening?

It looks like skies are very likely to become clear by sunset due to very dry air and good subsidence ahead of a high pressure ridge over southern Ontario Tuesday and Tuesday night, with the exception of some low clouds that may persist over some regions mainly close to the big lakes (due to moisture below a strong subsidence inversion) and increasing high cloudiness by morning (ahead of a low pressure trough that is west of the Great Lakes region during Tuesday).

Will skies be clear Monday evening over southern Ontario?

It looks like mostly clear skies are likely. Some patches of mid-level moisture and upward vertical motion are forecast to move across southern Ontario as a weak upper-level trough moves eastward from southern Ontario, but generally dry air and subsidence is forecast as a high pressure ridge builds eastward over the Great Lakes region overnight. The major exception is over regions east of Lake Huron, where lake-generated cloudiness may cause mostly cloudy skies.

So, in summary, mostly clear skies are likely over most regions of southern Ontario Monday evening.