'Like a volcanic eruption': B.C. wildfire triggers massive pyrocumulonimbus cloud

A pyrocumulonimbus cloud is seen in an image from Colorado State University's Cooperative Institute for Research in the Atmosphere on Aug. 16, 2023.

Smoke emanating from a wildfire in B.C.'s Southern Interior erupted into a massive pyrocumulonimbus cloud this week – and the explosive phenomenon was captured on video.

A clip of the eruption was shared on social media Wednesday by Colorado State University's Cooperative Institute for Research in the Atmosphere.

The striking video shows smoke billowing from the wildfire before a huge plume suddenly shoots into the sky.

Terri Lang, a meteorologist with Environment and Climate Change Canada, said pyrocumulonimbus clouds are similar to regular cumulonimbus clouds – dense formations that develop over hot surfaces – except they draw their heat from intense fires.

"If the heat is trapped, it can grow explosively," Lang said. "This one was particularly explosive. It almost looked like a volcanic eruption."

Pyrocumulonimbus clouds, like regular cumulonimbus clouds, are also capable of "spitting out lightning strikes," Lang added.

While the CIRA video does not identify the exact location of the cloud, Lang said it appears to have occurred near Cathedral Provincial Park, where dozens of campers were evacuated this week. 

The phenomena aren't uncommon during B.C.'s wildfire seasons, according to ECCC, though most are not as dramatic as the one captured Wednesday evening.

Lang recalled watching the Okanagan Mountain Park wildfire in 2003, when a pyrocumulonimbus cloud formed and delivered some rain onto the flames.

"It actually ended up slowing the fire a bit, but that's not always the case," Lang said. "It can also produce lightning and no rain at all, which can be quite detrimental."

The volatile conditions surrounding a pyrocumulonimbus cloud can also pose serious challenges for firefighters. The clouds cause intense updrafts, sucking up smoke and creating treacherous conditions for crews on the ground and in the air.

"Moving around something like that can be extremely difficult as the winds can be very strong," Lang said. "It just makes for even more dangerous conditions with our already volatile fire."