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Bomb Cyclones Explained: Causes, Impacts, and the Historic 2021 West Coast Storm

04:54 PM
November 19, 2024

Extreme weather explained
What is a bomb cyclone?

The WeatherRadar (left) and WindRadar (right) showing a potentially record-breaking bomb cyclone over North Pacific on Nov. 19, 2024.

Understand bomb cyclones, their rapid intensification, causes and effects. Learn how these powerful storms can bring significant impacts to our daily lives and learn how to stay ahead of them.

A bomb cyclone is a rapidly intensifying mid-latitude storm characterized by a significant drop in atmospheric pressure. Specifically, it occurs when a cyclone's central pressure decreases by at least 24 millibars within 24 hours, a process known as bombogenesis.

This rapid intensification often results from the collision of contrasting air masses, such as cold continental air meeting warm oceanic air, leading to severe weather conditions, including strong winds, heavy precipitation and coastal flooding.

A notable example of a bomb cyclone impacting the U.S. West Coast occurred in October 2021. This powerful storm underwent explosive intensification, reaching a minimum central pressure of 942 millibars, making it one of the most intense systems recorded in the Northeast Pacific.

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The cyclone brought heavy rainfall, strong winds, and significant flooding to parts of California and the Pacific Northwest, disrupting transportation and causing widespread power outages.

Due to their extreme nature and rapid intensification, bomb cyclones can be challenging to forecast. However, staying informed is crucial. With the Weather & Radar app, you can stay ahead of these powerful storms by signing up for Weather Alerts. Tap the link above to learn more.

Federico Di Catarina
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