Temperatures drop across Ontario with rounds of rain, storms on tap

Ontario will experience an unsettled weather pattern this week with multiple rounds of rain showers and thunderstorms expected. This will result in significant rainfall totals and temperatures remaining below seasonal norms

Ontario’s weather this week will be shaped by a significant upper-level low pressure system over central Canada. Several surface low pressure systems will pass through, bringing periods of showers and thunderstorms. Temperatures are forecast to remain seasonably cool, with highs in the low 20s. Normal temperatures for Toronto this time of year are 24°C.

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Baron - Atmospheric pattern - June 15

An unsettled week across Ontario with rounds of rain and thunderstorm chances

The week begins with the first system bringing showers and non-severe thunderstorms to northern Ontario, including areas from Kenora to Timmins, Kapuskasing, and Wawa.

Southern Ontario will enjoy a sunny, but cooler, start to the week.

Baron - Ontario precipitation Tuesday 3 pm - June 15

A second low pressure system arrives Tuesday, spreading showers and thunderstorms into northeastern Ontario with its warm front.

Southern Ontario could also see isolated pop-up showers and thunderstorms in the afternoon and evening as a cold front moves closer. Regions near Georgian Bay and Lake Huron may experience stronger thunderstorms, with heavy rain, gusty winds, and small hail.

Baron - Ontario thunderstorm risk Tuesday - June 15

By Tuesday night into Wednesday morning, the cold front will bring widespread showers.

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Higher moisture levels on Wednesday night may lead to heavy rain and stronger thunderstorms with localized flooding risks.

Baron - Ontario atmospheric moisture Wednesday - June 15

Gusty winds are expected in southwestern Ontario and the Niagara Region.

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Another round of showers and thunderstorms is forecast for Thursday, along with windy conditions as the front passes. Stay alert for heavy rainfall, potential flooding, and hazardous road conditions.

Baron - Ontario winds Thursday afternoon - June 15

Unsettled, cooler-than-seasonal end to June

The remainder of June is expected to bring near-seasonal to slightly cooler-than-seasonal temperatures on most days. Conditions will remain occasionally unsettled, with rainfall amounts projected to be close to the seasonal average across much of the region.

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