Becoming drier and colder into December
The end of November will see a significant change starting to develop. It is going to stay unsettled for a few days, but high pressure will begin to build through the coming week, becoming well established next weekend.
This will mean a break from the frequently wet, windy and mild weather to a drier and colder set-up, with winds coming from the easterly and northerly quarters for much of the time.
There will be increasing instances of frost and fog as temperatures fall near or below the early-winter average, and it will become much drier. However, occasional showers are possible, chiefly in windward areas, so most likely over eastern parts of England and across the east and north of Scotland. This high pressure dominance will probably linger well into December, but things become very uncertain by Christmas; there are some hints that it could eventually slip farther south and open the door to milder, wetter flows from the west.
Wet and windy then turning drier and chillier
The weekend is going to be wet and windy but mild. Monday will be cooler, with further sharp showers scattered around. Most of these will be over Northern Ireland, western Scotland and western and southern parts of Wales and England. Early fog patches will dissipate to allow periods of sunshine elsewhere, but fog could return overnight. After a locally foggy and damp start, Tuesday will be a mostly dry day, but a lot of cloud could linger, and some fog patches might be rather slow to clear. As a result, it will feel rather chilly in places.
With high pressure continuing to build, Wednesday should be a largely dry day. Fog patches should lift more easily as winds pick up just a little, and with cloud breaking there should be some sunny breaks here and there. A frontal system in the Atlantic will try to edge eastwards as it weakens, and it could bring some patchy showery rain to some western areas, most likely Northern Ireland and the north and west of Scotland. Temperatures will be near average for the very end of autumn. As we head into December, high pressure looks like building over Scandinavia with a ridge towards the UK. There is some uncertainty regarding how quickly this high will develop and on its exact position. Atlantic fronts could bring a chance of some showery rain to northern and western areas around Thursday and Friday, but apart from that the rest of the week should see a lot of dry weather. However, it will feel rather cold, especially in the east, due to broadly easterly winds developing.
Mostly settled and rather cold
Early December should see the weather dominated by high pressure, most likely centred near Scandinavia initially, but perhaps drifting westwards towards Scotland. This will most likely mean a continuation of chilly wind flows from the easterly quarter at first, with temperatures for most of the UK near or below average for the start of winter. It could be a little milder across Scotland.
High pressure ordinarily means a lot of dry weather, but those easterly breezes will pick up moisture from the North Sea, which could bring some patchy showery rain to eastern coastal areas of Scotland and England. There might also be a slight risk of a few showers nudging northwards into southern England from the Continent for a while.
If high pressure does tend to edge westwards, then the wind direction will turn more northerly for a while, or even northwesterly. This would still be a chilly scenario, and would bring higher chances of some showery rain to Scotland, and high-elevation snow flurries, while showers could still affect eastern coastal areas. Elsewhere there should be a lot of dry weather but there will be risks of fog patches overnight where it is calm enough.
Staying mostly chilly but possibly milder later
Heading towards the middle of December, the high pressure dominance looks set to continue - at least for a while. Models have reasonable agreement on the overall pattern through to mid-month, with high pressure remaining dominant across northern Europe, still most likely centred between Scandinavia and Scotland.
So, we will probably see chilly eastern breezes lingering, occasionally becoming more north to northwesterly as the high centre potentially oscillates westwards and eastwards. Temperatures are most likely to stay near or a bit below the early-winter average, with risks of being a bit colder, as suggested by some of our analogues. Many areas will stay largely dry but often cloudy and occasionally foggy with perhaps a little drizzle. Northern and eastern Scotland along with eastern coastal parts of England would have the highest chances of occasional showery rain, with some wintriness over the Scottish Highlands - although we are not seeing any likelihood of significant snow yet.
As Christmas closes in, the picture becomes a lot more hazy, with models starting to diverge rather significantly. Some maintain the high pressure dominance but others make a complete switch and shift high pressure southwards, allowing Atlantic low pressure systems to finally return. Most likely the high pressure scenario will continue for a while, but before the last week of the month we could see this turnaround occurring. Christmas weather is therefore on the cusp, but we might be starting to see a change to milder and wetter conditions. Right now, uncertainty is very high.
We will see if there is any better clarity on the persistence or otherwise of high pressure and chilly weather up to Christmas. Will we have risks of even more frigid air, or will it turn milder?