Bomb cyclone: What is the weather phenomenon slamming B.C. and U.S.?
More than half a million Americans and 100,000 British Columbia residents were without power on Wednesday morning as they grappled with a weather phenomenon known as a “bomb cyclone.”
The powerful storm swept across the northwest U.S., battering the region with strong winds and rain, causing widespread power outages and downing trees, killing at least one person.
In B.C., highways closed, trees were downed and many remained without power Wednesday.
But what is a bomb cyclone?
Global News chief meteorologist Anthony Farnell said the phenomenon is not new.
“This is something that has recently become very popular on social media, but it’s actually a meteorological term that has been around for decades,” Farnell said.
Meteorologists Fred Sanders and John Gyakum gave this pattern its name in a 1980 study.
A bomb cyclone is a large, intense mid-latitude storm that has low pressure at its centre, weather fronts and an array of associated weather, from blizzards to severe thunderstorms to heavy precipitation.
According to the U.S. National Oceanic and Atmospheric Administration (NOAA), bombogenesis, a term used by meteorologists, occurs when a mid-latitude (the latitudes between the tropics and polar regions) cyclone rapidly intensifies, or strengthens, over a 24-hour period.
“When you have a rapidly intensifying cyclone that deepens 24 millibars in 24 hours or less, so about a millibars per hour, that would be a bomb cyclone. This more than doubled that. In fact, it almost tripled it — 66 millibars in 24 hours,” Farnell said.
Bombogenesis can happen when a cold air mass collides with a warm air mass, such as air over warm ocean waters, according to NOAA. It is popularly referred to as a bomb cyclone.
Most cyclones don’t
Read more on globalnews.ca
