March shows off spring-like side in Ontario with mid-week thunderstorm risk
You know spring is right around the corner when we start talking about thundertorm potential in Canada. A strong low will trigger severe weather stateside this week, including the chance of tornadoes, with even a few rumbles of thunder possible in southern Ontario
You can sense winter is almost behind us when we start talking about thunderstorms in the forecast in Canada.
The risk of thunderstorms appears in southern Ontario on Wednesday as a potent Colorado low will help to usher in mild air and instability into the region. The same system will also be responsible for bringing heavy snow in northern Ontario.
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The large, sprawling storm sweeping across North America will be expansive in the thunderstorm potential, ranging from Mississippi to Mississauga, Ont.
The greater threat for severe weather, however, will remain far south of the border.
Before making its way into Ontario, the storm will bring the potential of a few strong tornadoes to eastern portions of the southern end of the Plains, reaching into the lower Mississippi Valley and southeastern sections of the U.S. on Tuesday.
Wednesday, under the warm front, could see some of that thunderstorm energy sneak into southern Ontario, including the Greater Toronto Area (GTA). Embedded thunderstorms are forecast alongside the heavy rain.
The warmth and incoming bout of rain won't be good news for local watersheds.
Due to the snowmelt, rain and frozen ground, localized flooding will be a factor. The risk is compounded by very mild air in the southwest, with temperatures potentially hitting the mid-teens in Windsor and Niagara region.
Strong dynamics are at play with the Ontario thunderstorm risk, including a negative-tilted jet stream, strong warm and cold air masses, with abundant moisture to work with from the Gulf of Mexico.
Stay tuned to The Weather Network for the latest forecast updates for Ontario.
With files from Rachel Modestino, a meteorologist at The Weather Network, and Nathan Howes, a digital journalist at The Weather Network.