A weather phenomenon known as a microburst delivered significant damage to the Carleton North High School in Florenceville-Bristol, N.B. and the nearby community of Greenfield, said Jill Maepea, a warning preparedness meteorologist with the Department of Environment and Climate Change Canada.
Maepea said while the damage could resemble that left behind by a tornado, it appears more likely a microburst hit the northern Carleton County region late Wednesday evening, June 30.
Maepea said microbursts are not uncommon as part of severe thunderstorms in New Brunswick and can damage a small area significantly. She added it could also move with the storm.
She explained a microburst is a sudden downdraft of air that could create intense winds over a limited area.
Accuweather describes a microburst as follows:
"A microburst is a small column of exceptionally intense and localized sinking air that results in a violent outrush of air at the ground. It is capable of producing damaging straight-line winds of more than 100 mph (160 km) that are similar to that in some tornadoes but without the tornado's rotation."
Maepea said the Forenceville-Bristol-area weather event was one of several severe thunderstorms across the province on Wednesday.
Erica Smith, a resident of Greenfield Road near Florenceville-Bristol, said as her family was watching television as they noticed the winds growing "stronger and stronger."
"And then you'd hear cracks and stuff, and then it eventually calmed down," she said.
The Smith home lost power. When they ventured outside, it was easy to see why. The violent winds knocked over trees onto the power lines to their home.
"It ripped the (power) mast right off the roof," she said.
The storm uprooted trees along much of Greenfield Road. Many of the trees landed on power lines. Starting at 2:30 a.m. July 1, N.B. Power crews spent most of Canada Day trying to restore power to the community.
At the Carleton North High School, winds from the microburst ripped off a portion of the roof above the skilled trades and arts department and damaged several parts of the building.
"Debris from the event was scattered across the teacher parking lot, the lawns, and into the tree line adjacent to school property," Principal Jason Smith told the River Valley Sun. "Water damage has occurred in the hallway in this wing of the school as well as the adjacent classrooms. The extent of the damage is under assessment."
Anglophone West School District staff joined representatives from the Department of Education and Early Childhood Learning and the Department of Transportation and Infrastructure at the school on Thursday morning.
Flavio Nienow, a communications officer with the Department of Education and Early Childhood Learning, said officials are thankful no one was at the school with the microburst hit. Following the incident, he said, officials took immediate action to minimize damage, including setting up measures to control water infiltration.
"Fortunately, the vapour barrier below the roof insulation remained primarily intact, minimizing damage to the school," Nienow said. "Next week, contractors will demolish the roof down to the impacted area's vapour barrier and ensure that the roof is watertight."
He said officials from the Department of Education and Early Childhood Development and the Department of Transportation and Infrastructure are working with Anglophone West School District to assess the extent of the damage and plan for the necessary repairs to rehabilitate the building.
Nienow said more information would become available once the engineering assessments are completed.
Wednesday's severe thunderstorms followed several days of above-average temperatures and high humidity.
Maepea said New Brunswick's weekend weather would see a drastic change with below-average temperatures forecast for Friday, Saturday and Sunday. She said temperatures would return to normal or above next week.
Jim Dumville, Local Journalism Initiative Reporter, River Valley Sun