Will skies be clear over southern Ontario Tuesday night?

Partly clearing skies are possible, due to a high pressure ridge spreading eastward over northern and southern Ontario with dry air and subsidence that may cause the cloud layer over southern Ontario to subside and result in partly clear skies in some locations. However, the substantial layer of moisture is not likely to subside and disperse easily, and probably will remain as a low overcast layer due to a subsidence inversion caused by the subsiding air ahead of the high pressure ridge. The strengthening subsidence inversion (illustrated below) will most likely trap the low-level moisture and prevent skies from clearing.

In summary, skies are most likely to remain cloudy but clear breaks may develop over some locations.