A state of emergency has been declared in Florida as Hurricane Dorian gathers speed of almost 150mph on its track towards the state. The potentially killer tempest, expected to make landfall early next week, is feared to become the worst of its kind since Hurricane Andrew killed 65 people in 1992. While its long-term track is uncertain there are signs Dorian may sweep towards the UK later in September giving the weather a shake-up.
The main impact would be to give the jet stream a ‘jolt’ triggering a period of wet and windy weather as energy remaining from the system gets caught up in Britain’s weather patterns.
Another outcome, which is being favoured by some long-range forecasters, is that it would encourage a period of warmer, more settled weather.
Remnants of previous Atlantic hurricanes have led to both scenarios depending on how far north their tail ends have clipped the UK.
While it is still early, experts say they are keeping an eye on the storm and its progress over the next week or so.
John Hammond, meteorologist for Weathertrending, said: “The bottom line is that by week two of September, this storm will have as yet unpredictable results for our weather.
“In the past, when ex-hurricanes have ‘jolted’ our jet stream, the impacts have ranged from disruptive wind and rain on the one hand to heatwaves on the other.
“I would not discount the prospect of another period of dry and warm weather later in the month.
“With shorter days and a weaker sun, such a spell would not match the heights of heat reached earlier through the summer.”
Weather models show a swathe of warm air flooding into the UK during the second half of the month pushing temperatures back into the mid-20Cs in parts.
Forecasters are, however, divided over the outlook with some predicting wet and windy weather until the end of the month.
Hurricane Dorian’s path through the next week will dictate how what’s left of the storm will affect the weather on this side of the Atlantic.
Met Office meteorologist Craig Snell said: “The five-day track of the storm is uncertain and it all depends on how it interacts with Florida, whether it moves inland or up the east coast of the US.
“If it did move towards the UK we would be looking at mid-September and if there are any repercussions across our neck of the woods, these would not happen until the second week of September.
“Hurricanes can do lots of different things, sometimes they do move up and start to interfere with the jet stream.
“This is just one scenario though, and at this stage it is too early to say exactly what it will do, it will be a case of wait and see.”
Some weather forecasters paint a less cheery picture for the start of autumn giving predictions of wind and rain through the rest of the month.
James Madden, forecaster for Exacta Weather, said: “We are looking at something much more unsettled and cooler compared to the past few weeks.
“This is the pattern which looks like it could persist through the second half of September and into October.
“There is the chance of some notable stormy periods and there is the risk of several significant low-pressure systems hitting our shores after developing and spinning off the east coast of the United States.”
Cooler temperatures will mark the start of autumn with the mercury set to drop 15C in parts of the country compared to last week.
High pressure will build to the west of the country allowing cooler air to sweep in from Iceland, according to the Met Office.
Mr Snell said: “The weather is right on cue for the start of autumn this week and we are looking at a much cooler spell compared to the very hot conditions last week.
“While it will be fairly quiet we could see temperatures between 10C and 15C lower than during the heatwave, dipping into single figures in parts of the country.
“High pressure will build to the west of the UK bringing in a northerly airflow.”