Severe thunderstorm warnings – Ontario's first for 2021, a few days shy of the "official" start of spring – were over much of southern Ontario, including the entire GTA, as a cold front sliced through the humidity and warmth, triggering the storms as it went. Behind the front, temperatures are expected to take a tumble into the weekend after daytime highs that reached the 20-degree mark in several communities. A more detailed look, below.
Severe thunderstorm warnings dropped by late Thursday evening
Calmer but cooler for Saturday, falling to near seasonal for the weekend
Next chance of storms early-mid next week
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THURSDAY: WARMTH PEAKS, SEVERE THUNDERSTORMS
Thursday afternoon saw the peak of this stretch of spring-like warmth, cracking 20°C in some communities, including London and St. Catharines, with double-digit highs for almost everyone else, including the east.
That warmth and humidity helped fuel a decidedly summer-like feature, however: Thunderstorms sparking as a cold front slid through the province, triggering severe thunderstorms as it went.
The first warnings were issued for some areas of the province around 3:30 p.m., including Parry Sound, Burk's Falls, and Algonquin Park, and eventually came to encompass most of the south of the province, including the entire GTA, before the last one dropped in the evening. Strong winds, heavy local downpours, and pea-sized hail were reported from the storms.
WEEKEND OUTLOOK: SUNNY, BUT COOLER
In the wake of Thursday's system, daytime highs will plummet to more seasonal values, sitting in the low single digits by Saturday.
While cooler, the weekend will still feature abundant sunshine, making for an overall pleasant mid-March feel. Next week will also start out much cooler, with forecasters eyeing a potential messy system.
"We're closely watching the system over the central U.S. to see if that will track far enough to the north to bring messy weather to the region on Tuesday/Wednesday, but it is possible that it will slide by to the south with strong high pressure over the region," Weather Network meteorologist Dr. Doug Gillham says.
Most of next week will be more seasonal, or on the cool side of seasonal for March. Forecasters are also watching the potential for a Texas Low to impact the region late next week.
Check back as we continue to monitor the forecast as we near closer to spring.