On September 7th, 2021, an EF2 tornado hit the town of Lucknow, Ontario. It was the result of a tornado that was embedded inside a linear complex of severe thunderstorms; us weather fans call it a QLCS, or quasi-linear convective system (you don't need to know more). The risk was no surprise to anyone following the potential for severe weather. It was scouted days before.

As proof, I made a Twitter thread highlighting a potent severe risk three days in advance.

While the risk for severe storms looked like a foregone conclusion, what was absolutely not clear was the risk for tornadoes. This event was cold front driven. Discrete cells (the most common tornado producers) did not look likely because of the strong forcing along the length of the front. Similar synoptic setups produce a long line of storms with damaging winds as the primary threat: not supercells. This doesn't eliminate the threat, but does make it far more unclear. In hindsight, the warm front setting up in the area of a storm merger (below) set the stage for what was a embedded cyclical supercell.

The tornado that hit Lucknow was likely the result of a line merger (storm mergers, and the results from them, are a highly complex area of study. You can get tornadoes produced from an event that likely wouldn't have produced one otherwise, or a merger will shut down what had a high risk of producing one. It's an area of study in its infancy).

The Chase

The above video shows the drive up to the shelf cloud on arrival to regional road 1, north of Lucknow. I left the house as the storms were ongoing over Lake Huron, so I wasn't going to be able to meet them at the shoreline. I decided on a target area near Amberley/Ripley. As I was driving NW on 86 and turned north on 1, the very pronounced shelf cloud became apparent. It was exceptionally low to the ground and carried strong outflow winds. Getting the picture above was problematic for keeping camera shake down. 

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At this point, after getting back to regional road 1 and facing south towards Lucknow, I knew the storm was producing a tornado to my south. The issue? It was a "rain wrapped" tornado, or a tornado wrapped in what looks like a wall of rain. You can't discern anything that looks tornadic visually. You can easily drive in, thinking it's rain, and get into trouble. I have seen what they look like when chasing storms in the US, so that helped me arrive at the conclusion that it was very likely a tornado.

The shelf cloud was NE to SW oriented. With the tornado moving nearly due east, this presented a logistics problem.

Ontario, in this area, has a grid road network, but it is diagonal in nature. A due east route or due south to parallel or get away from both the incoming shelf cloud and tornado was no longer going to be possible. I'd have to take the brunt of one, so...I chose the shelf cloud. It hit hard with strong wind gusts, hail that dented my car, and close range lightning. The video below shows both the tornado and the barrage of the shelf cloud.

My crude Google Map drawing and radar show that there was nowhere for me to avoid some part of it due to the diagonal road network.

After the storm had passed over me and dinged up my car with up to quarter sized hail, I decided to double back to Lucknow to check on the residents. I knew the tornado was likely to have passed close by, if not hit the town. I arrived and began to see the damage. (Twitter Link to Damage). A few power lines were down, trees were broken, but the great news was no reported injuries. I talked with a few people that were out on the street, confirmed they were okay, and asked if they needed anything. It turns out that the town was already helping each other. Considering the scare, it was a best possible outcome.

I'll enclose all pictures and video in the blog from the event. I'll also include the link to my interview with the Owen Sound Sun Times where I discuss the event.

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