Clouds and showers should clear out of the Seaway by 9 am allowing for the destabilization of the atmosphere and the formation of severe thunderstorms producing large hail and gusty winds.
It appears that the first round will occur early in the afternoon in extreme eastern Ontario into southeastern Quebec with later storms forming to the west. These storms should make their way into the Montreal area by the early evening hours.
Very meagre instability has already yielded a thunderstorm in Possum Lake this morning. 14.1 C; a good deal of CAPE should be in place if we make up to 20 C, which seems reasonable.