Will skies be clear over southern Ontario Thursday night?

Mostly cloudy skies seem likely, except for less cloudiness in regions near and north of GTA, and eastward over eastern Ontario. A region of moisture at lower and mid-levels (illustrated below) is forecast to move eastward over southern Ontario Thursday night ahead of a weak mid-level trough and this moisture is likely to appear as cloudiness. Regions near and east of GTA will likely have less cloudiness during the evening, until the moisture and cloudiness moves eastward over eastern parts of southern Ontario later in the evening.
In summary: partly clear skies near and east of GTA during early evening, mostly cloudy elsewhere over most of southern Ontario.