Potential April Fools’ Snowstorm for Eastern Ontario; Up to 12–20cm of Snowfall Accumulation Possible

If you live in Eastern Ontario, you might’ve felt left out this winter as it seemed like every significant storm missed the region or ended up on the warm side of a system resulting in heavy rainfall (as we saw for Christmas). Not so fast! Mother Nature is brewing a cruel April Fools’ joke for those in Eastern Ontario that just want to be over with winter and get started with spring. A moisture-laden system is expected to track up the US Eastern Seaboard between Wednesday and Thursday bringing a swath of messy weather to New York and New England as it clashes with colder air flooding in from the north. The latest data indicates that the northwestern precipitation bands could stretch into Extreme Eastern Ontario with heavy snow starting early Thursday morning and continuing throughout the day.

However, this storm is highly track-dependent and the models so far have been shifting with almost every update so keep in mind this forecast could change drastically even with 2 days to go. We feel it’s significant and consistent enough to warrant a preliminary forecast to outline what may happen even if it ends up tracking more to the east and misses Southern Ontario entirely. Stay tuned for our final forecast to be posted by late Wednesday where we should have more confidence on the track of the system.

After a relatively warm day on Tuesday, we’re expecting slightly colder daytime temperatures for Wednesday mostly as a result of scattered rain showered moving across Southern Ontario throughout the morning and afternoon hours. This will usher in even colder air behind it as it moves out plunging temperatures to near or below the freezing mark as we head into Wednesday night. The colder air will play a key role in the potential for significant snowfall across Eastern Ontario as precipitation from a system over New England pushes into the far eastern part of our province. Heavy snow is expected to begin to affect locations such as Brockville, Morrisburg and Cornwall predawn Thursday and will likely have a major impact on the morning community in this area. Later in the morning, it will expand even further to the northeast including Ottawa and Kingston although there is some uncertainty on how widespread the heavy snowfall will be. This will continue through the morning and early afternoon before the snow tapers off to some scattered flurries by the late afternoon.

As far as potential accumulation, this again will depend on the exact track of the system so expect some change. With that being said, we could see an area of accumulation ranging from 12-20cm extending from Brockville and along the international border toward Cornwall. There is some overachieving potential here and we could see some localized totals approach 25cm. For areas further east including Ottawa, Perth and Kingston we’re looking at final totals between 6-12cm although they may see only a few centimetres if the storm is more contained to the border. Surrounding regions and even into the Niagara Region could see around 2-6cm from this system with just trace amounts for the rest of Southern Ontario.

We will continue to watch this and issue a more detailed forecast when we have higher confidence in the track of the system. Stay tuned!