Rare November twisters touch down in New Brunswick to kick off the month

Despite Canada’s official tornado season ending in August, New Brunswickers in Harvey and Sheffield were treated to a late Halloween trick on Friday when a line of storms produced two tornadoes.

Even during the spring and summer months, tornadoes are seldom reported in New Brunswick. On average, the province only reports one tornado each year. Now, as of Nov. 4, there have been four total tornadoes reported for 2024.

So while New Brunswick tornadoes are rare, what’s even rarer are November tornadoes in Canada.

Since 2001, there have only been eight recorded tornadoes to touch down in November across the country. The latest-season tornado in this time frame was recorded on Nov. 23, 2013, near Prescott, Ont. The tornado was rated as an EF1.

According to the Northern Tornadoes Project (NTP), these recent tornadoes set a new record for the latest tornado events in New Brunswick, beating the previous record set on Sept. 21, 1965, when a pair of tornadoes touched down in the Grand Falls area.

Fall tornadoes may be rare in Canada, but they are much more commonplace for our neighbours south of the border.

In the fall, cold, continental air clashes with the humid Gulf air over the southeastern United States. This clash fuels powerful thunderstorms over the region, often resulting in deadly tornado outbreaks.

In Canada, we don’t typically have the Gulf’s tropical air reach this far north—especially in the fall and winter. Therefore, there is no warm, humid air available for our cold, Arctic air to clash with.

On Nov. 1, however, a system of thunderstorms was produced following an abnormally warm end to October in the Maritimes. The summer-like heat broke records across Eastern Canada for the warmest Halloween, but was quickly brought back to seasonal by a strong cold front associated with a low-pressure system that quickly swept into the Maritimes.

The team at NTP will be conducting surveys on Tuesday to assess the damage caused by the twisters and to give them official ratings.