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<\/p>\nTuesday is shaping up to be a stormy day in southern Ontario.<\/p>\n
Environment Canada has issued an updated weather outlook, which says that two rounds of thunderstorms are expected to sweep through a large part of the region.<\/p>\n
First round of storms<\/p>\n
During the overnight hours, parts of southwestern Ontario from Goderich to Niagara, including portions of the Greater Toronto Area, are expected to get the hardest hit (location A on the map below).<\/p>\n
\u201cA first wave of thunderstorms will primarily affect this area with heavy rainfall being the main threat,\u201d forecasters said.<\/p>\n
\u201cUp to toonie-size hail may be possible in the strongest storms.\u201d<\/p>\n
Up to 40 mm of rain is possible in those areas with the first round of storms, with local peak hourly rainfall of 20 to 30 mm, forecasters indicated.<\/p>\n
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Flash flooding, water pooling on roads, and washouts near rivers and creeks is possible.<\/p>\n
\t\t\t\t \t\t\t\tEnvironment Canada Areas from Wiarton towards Trenton (location B) may also see storms overnight, but it is less likely.<\/p>\n \u201cThe chance for thunderstorms lessens as you move northeast of the main A area, however thunderstorms are still possible along with heavy rain,\u201d Environment Canada said.<\/p>\n Up to 25 mm is possible there, with a local peak hourly rate of 15 mm.<\/p>\n Far southwestern Ontario, including Windsor, (location C) could see storms early overnight, with up to 15 mm locally in total from the first round.<\/p>\n \u201cDuring the onset of thunderstorms in the evening and early overnight, parts of this area may receive strong thunderstorms. Strong wind gusts and small hail may be possible,\u201d the weather agency said for those areas.<\/p>\n Second round of storms may be \u2018severe\u2019<\/p>\n Come late Tuesday afternoon and evening, a large portion of southern Ontario, including the Greater Toronto Area, Hamilton, the Niagara Region, London, and Windsor (location A below) are expected to see a second round of storms.<\/p>\n \u201cAfter a break in precipitation late Tuesday morning and early afternoon, a second round of thunderstorms is expected and may reach severe potential,\u201d Environment Canada said.<\/p>\n \u201cUp to 90 km\/h (winds), up to toonie-size hail and heavy rain will be possible with these storms.\u201d<\/p>\n Up to 30 mm of rain is possible locally with a peak hourly rate of 20 to 30 mm.<\/p>\n![\"\"](\"https:\/\/www.insauga.com\/wp-content\/uploads\/2026\/03\/Screenshot-2026-03-30-153229.png\")
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