Near-Record Rainfall Approaching Ontario to Wrap Up 2024
A significant weather system is set to bring near-record rainfall to Ontario, with moisture levels not seen in nearly a decade.
Ontario, Canada, Rainfall, Weather System, Great Lakes
Toronto: It’s been almost ten years since we’ve had a storm like this at the end of the year. A low-pressure system is moving toward the Great Lakes, bringing a ton of moisture from the Gulf. By Sunday, Ontario could see near-record rainfall.
So, what’s the deal with this moisture? We measure it using something called precipitable water (PWAT). Basically, it tells us how much rain could fall if we squeezed all the moisture from a column of air. This Sunday, PWAT values are expected to hit over 30 mm, which is pretty wild for December.
Usually, this time of year, southern Ontario is much drier, averaging around 7 mm. So, this storm is going to be about 500% more moisture than normal. That’s a big deal!
Looking back, in December 2015, a weather balloon in Buffalo recorded 33 mm of moisture, leading to 20-30 mm of rain in the Greater Toronto Area. We might see similar amounts this time, with some areas possibly getting up to 40 mm.
Now, will this be the wettest December day ever? Probably not, but several places could land in the top five wettest days for December. For example, Toronto’s record is 40.9 mm from 1962, and Hamilton’s is 50.6 mm from 1990.
As for thunderstorms, the chances are slim due to the weak sun angle this time of year. We might see a few lightning strikes, but don’t expect a full-blown thunderstorm. Just keep an ear out for a rumble or two!
Stay tuned for more updates on this unusual weather event across Ontario!