A new map and the BBC hint at a wintry turn soon.
After a balmy opening to November, Londoners now face a sharp shift as forecasters flag a much colder spell. A new projection from WX Charts pinpoints the potential for the first snowfall over the capital in the coming days, while BBC weather guidance points to sleet and a frosty dawn. It is the first real jolt of winter for the city after weeks of gentle winds and drizzle.
The timing matters for anyone planning commutes, school runs and weekends outdoors. The BBC is already flagging a narrow window for sleet during the morning rush, and models show snow risk nudging close to London. The pattern looks messy, not dramatic. And that is where the intrigue lies.
London first snowfall date teased by WX Charts and what the BBC expects next
Fresh model output from WX Charts suggests snow could reach London in the early hours of Thursday 20 November. The same map points to wintry showers along the East Coast and higher chances across parts of Northern Ireland and Scotland. In short, the south sits on the knife-edge where rain can flip to sleet or a brief burst of snow.
The BBC backs up the chilly signal in its latest London outlook. It highlights a frosty start on Thursday with sleet possible from 6am to 9am and temperatures dipping to 2C. By lunchtime sunshine should break through, yet values are not expected to climb beyond 5C, so pavements and car windscreens will feel properly cold.
We also enter a broader cool down with more frequent rain between frontal gaps. That includes drizzle mixed with light winds, then spells of heavier rain as the week turns. It wont last, say some, but the day-to-day picture still looks raw for the time of year.
What about sleet itself. Think of it as a wintry mix where raindrops and snowflakes fall together. A tiny warming a few hundred feet up can melt flakes into drops before they reach the ground, which is why London often sees slushy showers while hills not far away turn white.
The BBC London forecast that signals sleet and a sharp drop in temperatures
The BBC day-by-day for London shows a clear slide from mild to chilly with a brief wintry flirt on Thursday. Here is the snapshot for the city based on the latest update with daytime highs in Celsius.
- Thursday 13 November drizzle and light winds 16C
- Friday 14 November heavy rain and a gentle breeze 14C
- Saturday 15 November light rain and light winds 13C
- Sunday 16 November light rain and a gentle breeze 11C
- Monday 17 November sunny and a gentle breeze 8C
- Tuesday 18 November drizzle and light winds 6C
- Wednesday 19 November light rain and light winds 7C
- Thursday 20 November sleet and light winds 6C
- Friday 21 November light rain and light winds 7C
- Saturday 22 November light rain and light winds 8C
- Sunday 23 November light rain and light winds 9C
Notice the step down from mid teens to single figures by Monday. Then a marginal day on Thursday when the air turns cold enough for sleet and a chance of something wintrier before noon. For London, that is usually the sweet spot for fleeting flakes.
Why snow flips to rain street by street in London according to Ian Currie
Snowfall in the capital rarely spreads evenly. One road can wake to bare tarmac while a neighbourhood a short drive away enjoys a dusting. The explanation sits in London’s microclimates and small changes in height that tip the balance between rain, sleet and snow.
Local weather expert Ian Currie told MyLondon: « Snow is very dependant on the of where you are. For every 50 feet, 15 metres or so, you get higher up there is an increased likelihood of an extra day of snow. So if you take parts of South Croydon for example, Sanderstead and Selsdon, you are likely to get 10 more days of snow a year there than parts in the north of Croydon. »
He continued with a reminder about short distances and big differences. « It can change that much in a small distance. Again out by Biggin Hill there is much more chance of getting snow than Streatham or Tooting for example. »
Mr Currie set out how small shifts in storm tracks and air temperature can upend a forecast for marginal snow in the south. « We’re talking about very dynamic, complex systems. A weather front could be thousands and thousands of miles away, but if it arrives just a little bit off the predicted path, the weather can be totally different.
« Snow is very hard to predict because in this country we’re so close to that critical point where the temperature drops enough for precipitation to fall as snow. In Sweden, you could safely predict that a weather front would bring snow, but here just a change of a couple of degrees could make the difference. »
For Londoners, that means keeping an eye on overnight temperatures and elevation. Higher spots such as Biggin Hill or the ridges around Sanderstead can sneak a few flurries while much of inner London sits under cold rain. It feels unfair, yet it is classic capital weather.
Is there any coordination with TfL for gritting if temps dip to 2C and sleet hits 6–9am? Bridges, overpasses and cycle lanes get treacherous fast. WX Charts hint at early-hours flakes on the 20th, but the BBC window overlaps the commute. Could we get specific trigger points for salting and whether bus diversions are possible? A little heads‑up could save a lot of slips.