Increased Frequency of Lightning Sightings in Nova Scotia Skies This Summer

Nova Scotia saw the most lightning strikes ever recorded in the province in the month of July, almost all of which came from a single weather event.

Environment Canada’s latest climate report shows that 26,194 lightning strikes were recorded in Nova Scotia in July.

A massive and persistent storm triggered 23,008 of those attacks between July 21 and 22, when record rainfall killed four people and triggered record flooding in the province.

The average number of lightning strikes in July in the province is 7,172.

“Everyone knows how exceptional [storm] it was in terms of rainfall, but definitely exceptional in terms of lightning as well,” said Ian Hubbard, a meteorologist for Environment Canada.

“He set a new record for the month of July and actually set it just in that two-day period.”

Hubbard notes that the data only covers cloud-to-ground lightning. Lightning that does not reach the surface or that falls from cloud to cloud is not included.

Environment Canada’s partial statistics for this month show that there have been 10,837 lightning strikes between August 1 and 14.

Nova Scotia Power is also tracking a significant increase in lightning strikes, according to a spokesperson for the utility.

Between 2018 and 2022, there was an average of 314 lightning-related outages per year. So far in 2023, there have been 959, more than triple the five-year average.

Numbers do not equal trend

Although this season has been a very active one for thunderstorms in the province, Hubbard said that doesn’t necessarily mean an upward trend in recent years.

“When we have an event, or a month like we just had in July, it really stands out to people because it’s so exceptional,” he said.

For example, in 2018 there were only 441 strikes detected in Nova Scotia for the month of July. The following year, it jumped to over 9,500.

“We see a lot of fluctuation… just between one year and the next. There was a big jump there, but we can’t look at these numbers and predict a trend,” Hubbard said.

Trend or not, the record number of lightning strikes is another facet of the historic July 21 storm that some climatologists call a “head scratcher.”

“It’s so outlier that if you were to graph it, you wouldn’t believe it,” said Dave Phillips, a senior climatologist at the federal weather agency.

“We have all these little dots that show the trend or the distribution of lightning and you have this one in the corner standing there like it doesn’t belong, and yet it’s real. It happened. And it was this year.”

‘This is not the last’

Climate change inevitably means more lightning in our future, Phillips said, because there is a direct correlation between the warmth of the atmosphere and the frequency of lightning.

Whether we will ever see as many one-day strikes as the storm on July 21 remains to be seen. But Phillips said the severity of that storm should be a wake-up call because it could happen again.

“You couldn’t have fabricated all the conditions that came together to produce the type of event that we saw, and yet we saw it,” he said.

A number of factors led to the storm being so prolonged and destructive, according to Phillips. A tropical air mass, warmer ocean temperatures, and high levels of currents due to an already rainier-than-average summer.

“The fact that these things have happened in the past, but perhaps not with the same intensity, duration and impact, tells us that this is not the last. No one can say if this is a thousand-year event, a a hundred years”. event, or it would happen next year… it’s possible and all the ducks can line up and give it a repeat.”