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.
Buckingham Palace previously only said the visit would happen “when diaries allow”, but Mr Trump told reporters on Thursday: “I think they are setting a date for September.”
“I don’t know how it can be bigger than the last one,” he said.
“The last one was incredible, but they say the next one will be even more important.”
Image: Sir Keir Starmer handed Trump the invite earlier this year. Pic: PA
Mr Trump will become the only elected political leader in modern times to be invited to two state visits by a British monarch.
The president called the UK a “great country” in his comments at the White House on Thursday and said it was “an honour to be a friend of King Charles and the family, William”.
His first state visit was in 2019, when he was hosted by the late Queen.
Second-term US presidents who have already made a state visit usually get tea or lunch with the monarch at Windsor Castle, as was the case for George W Bush and Barack Obama.
Image: The president was hosted by the Queen in June 2019. Pic: Reuters
But Mr Trump is set to get all the pomp and ceremony laid on again in his honour – with another state banquet likely at Buckingham Palace.
The Royal Family‘s soft power diplomacy is viewed as a way of currying favour with the president, who’s known for his love of the monarchy and links to the UK through his mother, who was born on the Isle of Lewis in Scotland.
It comes as the government seeks an economic deal with the US, in the hope of potentially lessening the impact of the president’s tariffs.
Four people are in hospital as police deal with an active shooter on a university campus in Florida.
Videos showed people running through traffic, fleeing the scene, around the time of the shooting at the student union at Florida State University’s campus in Tallahassee.
Local police were “on the scene or on the way”, according to an alert sent out by the school and students have been told to “shelter in place”.
The FBI is also said to be responding to the incident.
Image: Florida State University students wait for news amid an active shooter incident at the school.
Pic: AP/Kate Payne
In a statement, Tallahassee Memorial HealthCare said it was “actively receiving and caring for patients” from the incident.
“At this time, details are still unfolding, and we do not yet have specific information to share. However, we want to assure the community that our teams are fully mobilised and prepared to provide the highest level of care and support to all those affected,” it added.
President Donald Trump said he was fully briefed on the incident and described it as “a shame”.
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He added: “It’s a horrible thing. Horrible that things like this take place.”
Florida governor Ron DeSantis, in a statement posted on X, said: “Our prayers are with our FSU family and state law enforcement is actively responding.”
Ambulances, fire trucks and police vehicles raced to the campus around midday local time (5pm UK time) on Thursday.
As students streamed away from the area of the student union in their hundreds, some were visibly emotional and others were glued to their phones.
Dozens later gathered near the university’s music school, waiting for news.
Florida State University student Daniella Streety told NBC News of the chaos that unfolded at the scene.
She remained on lockdown in a campus building and said: “I did see them carry out one student in what looked like on a stretcher and kept them in the road until an ambulance was able to pick them up.”
Joshua Sirmans, 20, was in the university’s main library when he said alarms began going off warning of an active shooter.
Police escorted him and other students out of the library with their hands over their heads, he said.
This breaking news story is being updated and more details will be published shortly.
A US federal judge has warned that he could hold the Trump administration in contempt for violating his orders to turn around planes carrying deportees to El Salvador.
US District Judge James E. Boasberg said he had found “probable cause” to hold the administration in criminal contempt and warned he could refer the matter for prosecution if it does not “purge” its contempt.
If the government doesn’t purge the contempt, charges could be brought forward by the Justice Department, NBC News reported.
And if the executive-led Justice Department refused to prosecute the matter, Judge Boasberg said he would appoint another attorney to prosecute the contempt.
Mr Boasberg said the administration could “purge contempt by returning those who were sent to El Salvador prison, in violation of his order, to the US.
This, he said, “might avail themselves of their right to challenge their removability”.
“The Constitution does not tolerate wilful disobedience of judicial orders – especially by officials of a coordinate branch who have sworn an oath to uphold it,” the judge wrote.
Executive vs judicial
This marks a notable escalation in the ongoing tensions between the judicial and executive branches of the US government during Donald Trump’s second term.
Parts of the US president’s legislative programme have been halted by judges, as the administration strains against the restraints of the separation of powers.
Mr Trump previously called for Judge Boasberg to be impeached while the Justice Department claimed he overstepped his authority – both reflecting the administration’s attempts to overcome perceived obstacles to the implementation of its agenda.
Mr Trump’s administration has also argued it did not violate any orders.
It claimed the judge didn’t include a turnaround directive in his written order and said the planes had already left the US by the time the order came down.
‘Administrative error’
At the heart of the legal wrangling is Kilmar Abrego Garcia, a man who was sent to El Salvador by the Trump administration in March despite an immigration court order preventing his deportation.
Washington acknowledged that Mr Garcia was deported due to an “administrative error”.
The US Supreme Court has called on the administration to facilitate his return, upholding a court order by Judge Paula Xinis, but Trump officials have claimed that Mr Garcia has ties to the MS-13 gang.
Image: Kilmar Abrego Garcia. Pic: CASA/AP
Mr Garcia’s lawyers have argued there is no evidence of this.
This all comes after El Salvador’s President Nayib Bukele visited the White House earlier this week.
During his time with Mr Trump, Mr Bukele said that he would not return Mr Garcia, likening it to smuggling “a terrorist into the United States.”
Image: The US and El Salvador presidents in the Oval Office.
Pic: Reuters/Kevin Lamarque
Along with Mr Garcia, the Trump administration has deported hundreds of people, mostly Venezuelans, whom it claims are gang members without presenting evidence and without a trial.
Democrat senator travels to El Salvador
Meanwhile, Democratic senator Chris Van Hollen arrived in El Salvador on Wednesday, saying he would seek a meeting with the country’s officials to secure Mr Garcia’s release.
“I just arrived in San Salvador a little while ago and look forward to meeting with the US embassy team to discuss Mr. Abrego Garcia’s release,” Mr Van Hollen said on social media.
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