What Exactly Is a ‘Bomb Cyclone’ Anyway?
This post contains references to products from one or more of our advertisers. We may receive compensation when you click on links to those products. Terms apply to the offers listed on this page. For an explanation of our Advertising Policy, visit this page.
Much of the US east coast is being blanketed by a uniquely strong blizzard that’s cancelling thousands of flights, wreaking havoc on car travel and clearing out the skies of nearly all air traffic. Everyone keeps referring to this storm using the catchy “bomb cyclone” term. So, for those wondering, let’s explore exactly what a “bomb cyclone” is.
“Bomb cyclone” is a meteorological term that’s the combination of two meteorological terms. So, let’s break it down:
Cyclone: Simply speaking, a cyclone is just a big spinning storm with a low-pressure center. A hurricane (or typhoon if it’s in the South Pacific or Indian Ocean) is perhaps the most recognizable cyclone. But, unlike a hurricane, a generic cyclone doesn’t have to be in tropical/subtropical waters and have a “closed, low-level circulation.”
Bomb: This is the word that catches everyone’s attention — in particular the TSA agent near you when you complain about your flight cancellation. This term refers to a storm that undergoes a rapid intensification reflected as a drop in pressure of 24 millibars in 24 hours. The lower the pressure, the stronger the storm.
For reference, standard sea-level pressure is 1,013 millibars. 2017’s Tropical Storm Emily made landfall in Florida at 1,005 millibars, just 8 millibars below the average. On the extreme end of the spectrum, Hurricane Maria was the 10th most intense hurricane ever with 908 millibars. All of that to say: a drop of 24 millibars is quite substantial.
The United Kingdom’s Met Office — equivalent of the National Weather Service in the US — has perhaps the best 90-second explanation and illustration of a weather bomb:
So, does the storm blanketing the Northeast qualify as a bomb cyclone? Turns out that it’s practically the definition of one. Remember that the pressure only needs to drop 24 millibars in 24 hours. How did it do?
That’s right; this overachieving storm more than doubled its goal. Dropping 59 millibars in 24 hours, the storm currently measured at 951 millibars, leaving the storm just 11 millibars higher than Superstorm Sandy was measured at landfall.
Thankfully though, this bomb cyclone is expected to stay off of the coast. And that’s good as the storm effectively a “winter hurricane” — bringing strong winds and tall waves, but heavy snow instead of rain.
Featured image by Saul Loeb / Getty Images
WELCOME OFFER: 30,000 Points
TPG'S BONUS VALUATION*: $600
CARD HIGHLIGHTS: up to $100 annual CLEAR statement credit, up to $100 annual LoungeBuddy statement credit, 3x points on travel and transit, 3x points on restaurants worldwide
*Bonus value is an estimated value calculated by TPG and not the card issuer. View our latest valuations here.
- Earn 30,000 Membership Rewards® points after you spend $2,000 on purchases on your new Card in your first 3 months.
- Earn 3X Membership Rewards® points on all eligible travel, from subway swipes and window seats to hotel stays and city tours.
- Earn 3X Membership Rewards® points at restaurants worldwide.
- Receive up to $100 per year in statement credits when you use the American Express® Green Card to pay for your CLEAR® membership at select airports and stadiums across the U.S. and Permissible Biometric Scanning Technology terms: eye scanning, irises scanning and fingerprints scanning.
- Use the American Express® Green Card to purchase lounge access through LoungeBuddy to any of the lounges in the LoungeBuddy network – no memberships, elite statuses, or first class tickets required. Earn up to $100 in statement credits per calendar year on your LoungeBuddy purchases.
- No Foreign Transaction Fees.
- $150 Annual Fee.
- Terms Apply.
- See Rates & Fees