Though it might not sound like it, a “bomb cyclone” is a legitimate scientific term, so named because the rapid formation of the storm is like a bomb going off.
Millions of Americans have been warned to brace for a bomb cyclonewith blizzard conditions, wind chills and temperatures plunging as low as -45.6C (-50.1F) – cold enough to get frostbite in less than five minutes.
A bomb cycloneor “weather bomb” is a term used to describe a rapidly deepening area of low pressure.
“More correctly, it should be called explosive cyclogenesis, which is when the central pressure of a low pressure system falls dramatically – by 24 millibars in 24 hours,” Sky News weather presenter Kirsty McCabe said.
“These intense storms bring heavy precipitation and very strong winds. In the US right now, very cold Arctic air is being pulled in, with the freezing weather causing further complications.”
How does a bomb cyclone form?
The sudden change in pressure is due to interactions with a powerful jet stream, McCabe said.
“This is the fast-moving ribbon of air high in the atmosphere that steers our surface low pressure systems around.
“The contrast between cold, Arctic air in the north and warm, tropical air in the south has strengthened the jet stream, which in turn deepened the area of low pressure.”
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Image: Overnight lows from Friday night into Saturday morning (temperatures in Celsius)
Why is it called a bomb cyclone?
Meteorologists have likened the sudden drop in pressure to a bomb going off, using words such as “explosive cyclogenesis” and “bombogenesis” to describe the storm’s formation process.
The term specifically refers to the speed at which a storm forms, Daniel Swain, a climate scientist at the University of California, said.
“It doesn’t necessarily refer to the absolute strength of the storm system,” he said.
Does the UK get bomb cyclones?
The UK has experienced weather bombs, most famously the Great Storm of 1987.
Image: Wrapping up as snow begins to fall in St Louis, Missouri. Pic: AP
How does a bomb cyclone differ from a hurricane?
“All bomb cyclones are not hurricanes,” Mr Swain said. “But sometimes, they can take on characteristics that make them look an awful lot like hurricanes, with very strong winds, heavy precipitation and well-defined eye-like features in the middle.”
Hurricanes tend to form in tropical areas and are powered by warm seas. For this reason, they’re most common in the US in summer or early autumn, when seawater is warmest.
In contrast, bomb cyclones don’t need balmy ocean waters to form.
They can appear over land as well as the sea and are most common between late autumn and early spring, when warm tropical air bumps up against frigid Arctic air.
“They have to occur at a time of year when there is some possibility of both warm and cool air at the same time,” Mr Swain said. It’s the difference in temperature that fuels the drop in pressure.
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US set to suffer its coldest Christmas in more than 40 years
Are bomb cyclones dangerous?
It depends. Sometimes, bomb cyclones behave like conventional winter storms.
But sometimes they produce heavy flooding, blizzard conditions and wind speeds comparable to a Category 1 hurricane.
“Fundamentally, the impacts of a bomb cyclone are not necessarily different from other strong storm systems, except that the fast strengthening is usually a signature of a very powerful storm system,” Mr Swain said.
Much of the danger lies in the fact that bomb cyclones can take people by surprise, he added.
The UK and US have agreed a trade deal, with Sir Keir Starmer and Donald Trump confirming the announcement during a live televised phone call.
It is the first trade deal agreed after Mr Trump began his second presidential term in January, and after he imposed strict tariffs on countries around the world in April.
Sir Keir said the “first-of-a-kind” deal with the US will save thousands of jobs across the UK, boost British business and protect British industry.
• Lowering 27.5% tariff on British car exports to the US to 10%, affecting 100,000 vehicles each year
• UK steel and aluminium industries will no longer face any tariffs after they had 25% duties placed on them
• Beef exports allowed both ways
• UK to have “preferential treatment whatever happens in the future” on pharmaceuticals, the president said.
However, there is a still a 10% tariff on most UK goods imported into the US after Mr Trump imposed that duty on most countries’ exports last month.
Mr Trump said the “final details” of the agreement were still being “written up”.
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Watch full call with Trump and Starmer
Trade minister Douglas Alexander told parliament the UK has “committed to further negotiations on tariff reductions”.
MPs will be able to debate the deal and any legislation needed to implement it, he added.
Sir Keir said “this is a really fantastic, historic day” that will “boost trade between and across our countries”, while Mr Trump said the agreement would be a “great deal for both countries”.
The president said the deal will make both the UK and the US “much bigger in terms of trade” as he thanked Sir Keir, who he said has been “terrific for his partnership in this matter…we have a great relationship”.
Sir Keir said it was achieved by not playing politics, and insisted the UK can have good trade relations with both the US and the EU.
Red lines on beef and chicken
The PM said the UK had “red lines” on standards written into the agreement, particularly on agriculture.
Mr Alexander told the Commons: “Let me be clear that the imports of hormone-treated beef or chlorinated chicken will remain illegal.
“The deal we’ve signed today will protect British farmers and uphold our high animal welfare and environmental standards.”
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‘American beef is the safest’
US agriculture secretary Brooke Rollins said the deal will “exponentially increase our beef exports”, and added: “To be very clear, American beef is the safest, the best quality, and the crown jewel of American agriculture for the world.”
On whether the UK will have to accept all US beef and chicken, Mr Trump said: “They’ll take what they want, we have plenty of it, we have every type, we have every classification you can have.”
Hinting the US will move towards higher welfare practices, he said US health secretary Robert F Kennedy Jr “is doing a tremendous job and he’s probably heading toward your system with no chemical, no this, no that”.
‘A Diet Coke deal’
Previous UK governments have attempted – and failed – to secure a free trade agreement with the US, but Sir Keir had made it a high priority.
Conservative shadow trade secretary Andrew Griffith chastised the deal, saying the UK is still in the same category as Burundi and Bhutan.
“It’s a Diet Coke deal, not the real thing,” he told the Commons.
A man has been charged after allegedly harassing Hollywood actress Jennifer Aniston for two years before crashing his car through the front gate of her home, prosecutors have said.
Jimmy Wayne Carwyle, of New Albany, Mississippi, is accused of having repeatedly sent the Friends star unwanted voicemail, email and social media messages since 2023.
The 48-year-old is then alleged to have crashed his grey Chrysler PT Cruiser through the front gate of Aniston’s home in the wealthy Bel Air neighbourhood of Los Angeles early on Monday afternoon.
Prosecutors said the collision caused major damage.
Police have said Aniston was at home at the time.
A security guard stopped Carwyle on her driveway before police arrived and arrested him.
There were no reports of anyone being injured.
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Carwyle has been charged with felony stalking and vandalism, prosecutors said on Thursday.
He also faces an aggravating circumstance of the threat of great bodily harm, Los Angeles County district attorney Nathan Hochman said.
Carwyle, who has been held in jail since his arrest on Monday, is set to appear in court on Thursday.
His bail has been set at $150,000 dollars (£112,742).
He is facing up to three years in prison if he is convicted as charged.
“My office is committed to aggressively prosecuting those who stalk and terrorise others, ensuring they are held accountable,” Mr Hochman said in a statement.
Aniston bought her mid-century mansion in Bel Air on a 3.4-acre site for about 21 million dollars (£15.78m) in 2012, according to reporting by Architectural Digest.
She became one of the biggest stars on television in her 10 years on NBC’s Friends.
Aniston won an Emmy Award for best lead actress in a comedy for the role, and she has been nominated for nine more.
She has appeared in several Hollywood films and currently stars in The Morning Show on Apple TV+.
Image: The defendants hugged each other after being acquitted of the charges. Pic: Commercial Appeal/USA Today Network/AP
The 29-year-old’s death and a video of the incident – in which he cried out for his mother – sparked outrage in the US including nationwide protests and led to police reform.
Civil rights attorney Ben Crump, who represents Nichols’ family, described the verdicts as a “devastating miscarriage of justice”. In a statement, he added: “The world watched as Tyre Nichols was beaten to death by those sworn to protect and serve.”
Memphis District Attorney Steve Mulroy said he was “surprised that there wasn’t a single guilty verdict on any of the counts” including second-degree murder. He said Mr Nichols’ family “were devastated… I think they were outraged”.
Image: Former police officers Tadarrius Bean, Demetrius Haley, Justin Smith were accused of second-degree murder. Pic: Memphis Police Dept/AP
But despite the three defendants being acquitted of state charges during the trial in Memphis, they still face the prospect of years in prison after they were convicted of federal charges of witness tampering last year.
Two other former officers previously pleaded guilty in both state and federal court. Desmond Mills Jr. gave evidence as a prosecution witness, while Emmitt Martin was blamed for the majority of the violence.
Sentencing for all five officers is pending.
Image: Tyre Nichols’ death sparked street protests in January 2023 in Memphis and across the US. Pic: AP
Video evidence showed Mr Nichols was stopped in his car, yanked from his vehicle, pepper-sprayed and hit with a Taser. He broke free and ran away before the five police officers caught up with him again, and the beating took place.
Prosecutors argued that the officers used excessive, deadly force in trying to handcuff Mr Nichols and were criminally responsible for each others’ actions.
They also said the officers had a duty to intervene and stop the beating and tell medics that Mr Nichols had been hit repeatedly in the head, but they failed to do so.
The trial heard Mr Nichols suffered tears and bleeding in the brain and died from blunt force trauma.
The defence suggested Mr Nichols was on drugs, giving him the strength to fight off five strong officers, and was actively resisting arrest.
In December, the US Justice Department said a 17-month investigation showed the Memphis Police Department uses excessive force and discriminates against Black people.