London weather: Autumn chill forecast to arrive within days as temperature to plunge

Temperatures are set to drop in London in the week ahead, bringing an end to a run of warm weather at the start of autumn.
By Wednesday and Thursday, the afternoon high is forecast to be 15C, with temperatures falling as low as 9C overnight, according to BBC weather.
It will mark a significant change from the summer-like warmth that has brought temperatures of up to 28C over the last week.
Sunday, Monday and Tuesday will be the last days with temperatures over 20C for the forseeable future, with highs of 22C predicted.
Temperatures will then plummet to highs of 15C for several days before climbing slightly to around 18C at the weekend. Similar temperatures are predicted for the week after.
The change in temperatures will be stark compared to the record hot and dry summer.
If the thermometer fails to reach 20C anywhere in the UK, it will be the first time that has happened since 11 June.
The Met Office forecast until October 17 states: “Fine and dry weather, with a few showers in the north, will quickly give way to a more changeable period as weather systems move in from the Atlantic towards the end of next week and into the following weekend. These will bring spells of rain or showers to most areas, heavy at times (especially in the northwest) with some strong winds. However, there will still be some drier interludes between systems.
“Into the middle of the month, similarly changeable conditions are most likely, with a mixture of Atlantic weather systems interspersed with some drier, brighter spells. Temperatures will likely be near to or slightly below normal at first, perhaps becoming warmer later.”
The forecast for the second half of October states: “The second half of October will probably maintain a changeable pattern overall with weather systems often moving in from the Atlantic. These will bring showers or longer spells of rain, with the wettest and windiest weather in the northwest, drier in the southeast. There is a chance that a period of more widely dry conditions could develop for a time, but confidence in the details of this is low. Temperatures will probably be above average overall.”
Temperatures will fall after the Met Office issued an update on the polar vortex that could cause chaos in London and across the UK this winter.
An unprecedented “Godzilla” El Niño event is set to hit the capital this winter.
