Severe storms, potential funnel clouds in southern Ontario Thursday
Southern Ontario faces risk of severe storms and funnel clouds on Thursday
A low pressure system tracking over the Great Lakes is set to deliver widespread rain and scattered thunderstorms throughout Thursday. Some thunderstorms may become severe, with the risk of, large hail, funnel clouds, and even a tornado or two.
Storm activity is expected to intensify and redevelop during the afternoon and evening hours, so it'll be important to keep an eye on active weather alerts in your area.
Thursday: Risk of severe thunderstorms and funnel clouds
After periods of heavy rainfall during the morning, thunderstorms are forecast to redevelop Thursday afternoon and evening across southern Ontario. Some of these storms may reach severe limits, with conditions supporting the potential for large hail ranging from 2 to 3 cm in diameter and localized heavy downpours.
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Cold air in the upper atmosphere combining with warmer surface air will create an unstable environment, increasing the likelihood of isolated, pop-up thunderstorms. Southwestern Ontario and areas along the Lake Huron shoreline are particularly at risk for funnel clouds due to high lapse rates and cooler air at higher altitudes.
There is also a slight chance of a weak landspout tornado emerging in the region during the afternoon or evening hours.
Residents are advised to monitor local forecasts and be prepared for rapidly changing weather.
Southern Ontario can anticipate 5-15 mm of rainfall, with the potential for higher localized amounts in areas impacted by thunderstorms.
In addition, wind gusts of 30-50 km/h are expected from late morning through early evening, with locally stronger gusts possible (up to 80 km/h) during thunderstorms.
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A reminder: water-laden roads and reduced visibility could create challenging travel conditions.
Rainfall levels this June have already approached or surpassed monthly normals in several regions, including Toronto, Hamilton, and Wiarton, making this another active month for southern Ontario.
Toronto has picked up 80 mm so far, and the monthly normal average is 81 mm. In Hamilton, 103 mm has fallen so far, and the June normal is 78 mm.
Rising heat and humidity next week
After rain on Thursday, southern Ontario will see partly to mostly sunny skies this weekend, with a low chance of an isolated shower. Highs will reach the mid-20s on Saturday and the mid- to upper-20s by Sunday.
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Next week will definitely feel like summer, with temperatures ranging from seasonal to above seasonal for several days. Humidity levels will also rise, with the humidex potentially exceeding 40. However, there is some uncertainty regarding daytime highs as thunderstorms and cloud cover from upstream systems could moderate the heat. Warm and humid nights are likely regardless.
By the second week of July, temperatures are expected to trend back to seasonal or slightly below, with a shift toward a cooler pattern expected for mid- to late July. Check back in with The Weather Network on July 1st as we reveal what's in store weather-wise across Canada in our monthly outlook.
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Be sure to check back for the latest weather updates across Ontario.