A cold front will pass through E ON and S QC tomorrow morning, accompanied by a powerful low-level jet and marginal CAPE.
850 mb winds reach 75 kt in parts of eastern Ontario in the morning hours, equivalent to around 135 km/h. Substantial transfer momentum from low-topped heavy downpours and marginal lapse rates will be sufficient for damaging wind gusts in excess of 90 km/h on a large scale.
Supercells may form in the strongly-sheared, strongly-forced environment, particularly as the morning progresses and the boundary layer destabilizes.
In stark contrast, the afternoon hours in the region should be mainly sunny and dry.