We are watching a moderate risk for some isolated severe thunderstorms across portions of Eastern and Northeastern Ontario including Southern Quebec.
Southern Ontario:
Hot and humid conditions will favor the development of some pop-up thunderstorms across Southwestern Ontario this afternoon and into the evening as defined lake-breezes set up along Lake Huron, Erie and Ontario. Alongside this, pop-up thunderstorms along and ahead of a cold front are possible in Northeastern and Far Eastern Ontario.
Areas highlighted in yellow or marked with a '3' have a moderate risk for some severe thunderstorms. This includes Hawkesbury and Ottawa extending northwest along the Ottawa river to include Pembroke, Stonecliffe, and Mattawa. Further west, there is a low risk for some severe thunderstorms extending from Cornwall through Maxville over to Algonquin Park and Monetville. This is highlighted in green and marked with a '2'. Finally, elsewhere, non-severe thunderstorms are possible. This is highlighted in blue and marked with a '1'. Extending from Tobermory through to Gravenhurt, Apsley and Belleville, including everything west and south, there is a low risk for an isolated severe thunderstorm.
The main threats in the yellow and green regions include wind gusts between 70 and 90km/h, hail between 0.5 and 1.5cm, locally 2cm as well as heavy rain over 50mm.
The main threats in the 'area of interest' include wind gusts between 60 and 80km/h, locally 90km/h, small hail and heavy rain over 50mm. Elsewhere, small hail, some brief gusty winds and some moderate to heavy rain is possible.
It is possible that areas within the blue region do see a severe thunderstorm today. The lake-breeze storms will be moving rather slowly, therefore, there is an enhanced rainfall risk.
Most of the thunderstorms today will be limited and isolated, many places will not see a thunderstorm today despite being highlighted on the map.
Northern Ontario:
Pop-up thunderstorms along and ahead of a cold front are possible in Northeastern and Far Eastern Ontario.
Areas highlighted in yellow or marked with a '3' have a moderate risk for some severe thunderstorms. This includes Mattawa extending inland towards Sudbury and Ruel as well as including Englehart, Temiskaming Shores and North Bay. Further west, there is a low risk for some severe thunderstorms extending from Monetville through to Sultan and Chapleau, including Timmins and Kirkland Lake. There is some question as to how far north storms will develop. Either way, we have included Kapuskasing and Cochrane in this risk area as well. This is highlighted in green and marked with a '2'. Finally, elsewhere, non-severe thunderstorms are possible. This is highlighted in blue and marked with a '1'.
The main threats in the yellow and green regions include wind gusts between 70 and 90km/h, hail between 0.5 and 1.5cm, locally 2cm as well as heavy rain over 50mm. Isolated cells could form a line of thunderstorms which may increase wind gusts towards 100km/h.
Southern Quebec:
Pop-up thunderstorms along and ahead of a cold front are possible in Northeastern and Far Eastern Ontario.
Areas highlighted in yellow or marked with a '3' have a moderate risk for some severe thunderstorms. This includes Angliers through to Dorval-Lodge, Le Flash and Rigaud, including everything south and west such as Lac-Caugnawana and Gatineau. Further east, there is a low risk for some severe thunderstorms extending from Stanstead and Quebec City north towards Timbrell and Obedjiwan. Many of This is highlighted in green and marked with a '2'. Finally, elsewhere, non-severe thunderstorms are possible. This is highlighted in blue and marked with a '1'.
The main threats in the yellow and green regions include wind gusts between 70 and 90km/h, hail between 0.5 and 1.5cm, locally 2cm as well as heavy rain over 50mm. Isolated cells could form a line or two of thunderstorms which may increase wind gusts towards 100km/h.
Most of the thunderstorms today will be limited and isolated, many places will not see a thunderstorm today despite being highlighted on the map.
We will be watching all these areas closely today and monitor the flash flooding risk.