Conditions will become favourable for the development of severe thunderstorms for a large area across Southwestern, Southern, Central and Eastern Ontario for Thursday, July 5th.
What to Expect
With continued rising temperatures, high dew-points, and daytime heating, a weak front will slice through the aforementioned regions and provide enough instability to bring-about some severe thunderstorms later in the day on Thursday.
While the dynamics are not entirely conducive to significant supercell development, a lack of shear, ultimately, will mitigate rapid intensification and development. The primary risk therefore, with these thunderstorms, will be quick flooding rains (25-50mm).
The greatest threat for severe thunderstorms will likely occur just east of Lake Huron, but likely 15-20km west of the major 401 corridor. The GTA and QEW should remain non-severe (overall) and regions around Cottage Country should receive rain showers.
1 or 2 severe thunderstorms on the northern edge of Lake Ontario cannot be ruled out.
A brief / slight cool-down (24-27C; less humid; and drier conditions), will arrive for the aforementioned regions on/for Friday, Saturday and Sunday.
From te brief cool-down outlined above, temperatures are expected to rebound back into the upper 20s and low 30s for the next severel weeks (avg: 29-32C). This time around however, conditions will be less humid than the more recent surge of warmth.
As outlined in our summer prediction, isolated severe thunderstorms will continue across Ontario and Quebec for much of the summer.
Long-Range Outlook: Manitoba, Ontario and Quebec.
Continued above normal temperatures and relatively dry conditions are still expected for Manitoba, Ontario and Quebec. There is some potential for record-breaking heat once again somewhere in the last few days of July into early August for about a week.
Remember, summer thunderstorm forecasts – severe and/or non-severe – represent a plausible scenario based on extensive weather calculations, parameters and up-to-date atmospheric data. Nothing is for certain, but outlines a possible or likely scenario based on the aforementioned points.
Please stay tuned, as we at TCW are monitoring this situation attentively.
Drive safe and always be alert during hazardous conditions.
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