‘Cool and unsettled weather’ returns to Toronto and it isn’t going anywhere - CP24

An upper-level trough and abundant, tropical moisture will lead to significant rainfall for parts of the Prairies this weekend, creating localized flooding concerns. Rainfall totals of 40-80+mm will affect a large swath of the region through Tuesday, with areas that see thunderstorm activity possibly exceeding 100 mm of accumulation. DON’T MISS: Canada’s Labour Day weekend holds heavy rain and sunny skiesOn Sunday, forecasters will be watching the Saskatchewan-Manitoba border for the potential of severe storms, including the chance of supercells and a low, but non-zero, tornado risk. Risk of severe storms on SundayWet and unsettled conditions are expected across Alberta on Sunday as periods of rain continue, especially in southern areas. Farther east, in Saskatchewan and Manitoba, thunderstorms moved through Sunday morning and will continue to be a risk in the afternoon and evening as they move into the latter province. For areas around the Saskatchewan-Manitoba border we are watching for the risk of stronger storms, with the chance for supercells to develop. That will bring all severe weather risks on the table, even a low, but non-zero, tornado risk.

Stick around any town long enough during storm season and you'll probably hear a bit of local lore about how the community is protected from twisters. “They just can’t happen around here,” the legends will insist, attributing this alleged immunity to rivers, mountains, or even tall buildings that disrupt a thunderstorm and stifle any attempt to spawn a tornado. Unfortunately, those myths aren’t just wrong—they’re flat out dangerous. Tornadoes are possible just about anywhere on Earth given the right conditions. Some areas are more prone to twisters than others, but we’ve seen formidable tornadoes touch down in areas where it didn’t seem like they could ever hit. DON’T MISS: Don’t fall victim to these seven dangerous tornado mythsTornadoes can and do strike citiesTens of thousands of spectators filled the Georgia Dome on the night of March 14, 2008, gripped by the tension of a college basketball tournament game thrown into overtime. As the teams duked it out on the court, the roof above the packed stadium began to shudder against the winds of an EF-2 tornado barreling through downtown Atlanta.

An October nor'easter is developing in the Atlantic, where it will bring high surf, rip currents, coastal flooding, winds and rain to parts of the East Coast for several days this week. The National Hurricane Center has it highlighted as an area to watch this week for potential subtropical development. However, regardless of development, this system will bring dangerous conditions to the East Coast this week. Fortunately, this system doesn't look to be as strong as the one in September. But the bad news? It could linger for much of the week, so impacts could have a longer duration than you would think. There are currently coastal flood alerts across parts of coastal North Carolina and Virginia, where anywhere from 1 to 4 feet of inundation is possible. Key takeawaysWe do not expect this storm to be as strong as the late September nor'easter. The area most likely impacted the longest appears to be from the Delmarva Peninsula to eastern North Carolina, with more models pointing to primarily eastern North Carolina.