This afternoon, thunderstorms will develop in southwestern Quebec and slide southeast into the St. Lawrence Valley. CAPE and shear values will be similar (if not more favourable than) to yesterday’s which yielded some severe weather (wind and hail) so it is imperative that more marginally large hail and gusty winds are to be expected today.
Today will be the last day of the prolonged cold-core severe weather event that has plagued eastern Canada since Saturday. We can look forward to more traditional warm-season severe weather starting Friday in southern Ontario then moving north for Canada Day.
12Z HRRR image for 4 pm this afternoon. It depicts two clusters of severe storms sliding through the province, both indicated by black outlines that indicate updraft helicities => 45 m2/s2.