Wednesday 13 Jan - Friday 22 Jan

Most likely unsettled with rain and hill snow spreading north and east on Wednesday. Drier conditions following later in the week but with a chance of further spells of rain arriving from the west. Mild in the south and west, and colder further north and east. Into the following week, rather unsettled conditions with spells of rain and perhaps strong winds will cross the UK at times. The heaviest and most prolonged periods of rainfall are more likely in the south and west. Drier and more settled conditions are more likely in the north and east. Temperatures are uncertain with colder weather more likely in the north and east and milder conditions in the south and west. However, there is a chance of cold spells for all areas.

Friday 22 Jan - Friday 5 Feb

Confidence for this period is low, though there is a signal for weaker than average westerly winds with Atlantic systems likely to track further south than normal. Therefore, for the north of the UK it is expected to be drier than normal with temperatures around average to a little below. Further south there is an increased chance of unsettled conditions, with above average precipitation and with temperatures slightly above average. Through this period there is a greater than average chance of cold spells across the UK with the associated risk of wintry hazards. There is potential at times for significant snowfall on the boundary between milder and colder air masses, with greatest risk across central and northern areas.

https://www.metoffice.gov.uk/

Yet another change , a decent update there 

Hmmm, I'm not sure about that. The GFS op runs this morning seemed to indicate everywhere turning milder but ECM seemed to be going down a different road. Still too early to be particularly confident one way or the other just now, IMO.

In the 18:30 forecast the summary for next week had changed to 'less cold for a time' suggesting that now they don't think the milder weather will 'win out'.

Indeed. I commented earlier today that the forecasts last night seemed to be overplaying the idea of mild weather.  

It's remembering that only last Sunday the forecasters were unsure about how the end of the week would shape up; and in terms of how active the frontal troughs wouldn't be they were wrong just 24 hours out.

I sense that the models are going to struggle again in a potentially knife edge evolution for our part of the Northern Hemisphere; whatever signals might have been there for a tropical maritime airmass to dominate must have faded somewhat overnight - which would seem to match up with the output us mere mortals can see.

Agreed , the 21:55 from Stav showed the cold air eventually winning 

BBC monthly outlook

Summary

Turning unsettled with increasing risk of cold.

_________________________________

Saturday 9 January – Sunday 17 January

Less cold, but some large temperature swings.

This weekend, we will see a change in the recent very cold but mostly drier than normal weather pattern that has stuck around for the past week. We will see low pressure systems move in from the northwest bringing some wetter, cloudier, and less cold air throughout the country. Lowland and hill snow chances will fade for a time, although the northern Scottish Highlands will still see some hill snow.  Temperatures will be nearer to normal, but likely still feel a touch colder than usual. Heading into next working week, the weather is expected to become a bit changeable.

As low pressure slides across Scandinavia, we will likely see the first half of the week bring some milder air. Although, some chilly nights are still likely with frost for many. Colder weather is expected around midweek, with the end of the week and weekend seeing chances for another mild spell. It will also tend to be wetter than normal with low pressure systems bringing frequent bands of rain in. There is a growing risk of some snow later in the week. But there is still a lot of uncertainty on the day-to-day specifics as the UK sits between the two dominant weather systems for Europe. So in short, we expect a volatile week of temperature swings and frequent rain, along with a chance of some snow in places later.

Monday 18 January – Sunday 24 January

Wetter weather with some volatile temperatures.

As we enter late-January, the forecast gets a bit more complicated. There are some strong signals for possible return of low pressure track, which would bring milder but wetter and windier weather. However, this comes with a rather large caveat, the polar vortex. This is a circulation of winds in the stratosphere, about 40-60 kilometres above the surface, and typically keeps cold Arctic air trapped at the pole. In early January, the vortex weakened and became displaced over Europe, and it's still overhead now. It usually takes a few weeks for the effects to reach the surface, so around mid-to-late January we expect an increased chance of cold outbreaks. At the moment, it looks like the coldest weather will miss us to the east, staying in Scandinavia and West Russia.

There is still a lot of uncertainty on the westward extent of the cold air, and we could see a few cold blasts mixed in with our overall milder, wetter weather. As a result, this week is likely to continue to see some volatile swings in temperature along with some wet and windy days. Fronts moving in over a cold snap will bring a chance of snow, even to low levels, but it is still too far away to pick out the specifics. Confidence is medium on the forecast, mainly due to the uncertainty in the temperatures. There is risk of more widespread cold, as we have seen in previous years with a displaced polar vortex.

Monday 25 January – Sunday 7 February

Unsettled and milder with a risk of cold.

Towards the end of January and into early February, there continues to be strong signals for a return of low pressure tracks from the south bringing wetter, windier, and milder conditions. This will be coupled with the polar vortex strengthening again back to normal levels by the end of the month. Although, there is still a delay in the impacts reaching the surface, so cold outbreaks are still possible into early-February. As with the previous week, we expect the cold to mostly stay to the east of us and low pressure to be the dominant feature, especially in February.

The UK will tend to find itself on the boundary between the cold high pressure to the east and the milder low pressure to the west, so confidence is pretty low. A minor shift in the weather pattern will lead to some large changes in the expected conditions for the UK, so some caution is needed at this range. In general, it will likely be on the milder side of average with frequently wet and windy weather, along with 1-2 day cold snaps bringing frost and a chance of wintry weather at times.

Further ahead

We will monitor the weak polar vortex and see if we can more accurately pin down where the coldest conditions in North Europe will be.

https://www.bbc.co.uk/weather/outlook

Update: ❄️❄️@MADRID now people skiing in the street #Filomenamadrid pic.twitter.com/rujxzRYUx5

— .Fernando. (@fernandoUKinney) January 9, 2021

Thursday 14 Jan - Saturday 23 Jan

Most likely unsettled with rain and hill snow spreading north and east on Wednesday. Drier conditions following later in the week but with a chance of further spells of rain arriving from the west. Mild in the south and west, and colder further north and east. Into the following week, rather unsettled conditions with spells of rain and perhaps strong winds will cross the UK at times. The heaviest and most prolonged periods of rainfall are more likely in the south and west. Drier and more settled conditions are more likely in the north and east. Temperatures are uncertain with colder weather more likely in the north and east and milder conditions in the south and west. However, there is a chance of cold spells for all areas.

Saturday 23 Jan - Saturday 6 Feb

Confidence for this period is low, though there is a signal for weaker than average westerly winds with Atlantic systems likely to track further south than normal. Therefore, for the north of the UK it is expected to be drier than normal with temperatures around average to a little below. Further south there is an increased chance of unsettled conditions, with above average precipitation and with temperatures slightly above average. Through this period there is a greater than average chance of cold spells across the UK with the associated risk of wintry hazards. There is potential at times for significant snowfall on the boundary between milder and colder air masses, with greatest risk across central and northern areas.

https://www.metoffice.gov.uk/

Was it Darren Bett? 

I think METO are struggling like the rest of us judging by this update, saving there bigger changes for tomorrow?

Friday 15 Jan - Sunday 24 Jan

A dry day for most on Friday before outbreaks of rain spread from the northwest later in the day. Over the weekend and into the following week rather unsettled conditions will develop across the UK. This will bring spells of rain to many areas, these perhaps accompanied by strong winds at times. The heaviest and most prolonged periods of rainfall are likely to affect the south and west, with the best of any drier conditions more likely in the north and east. Some snow is also likely at times in the north, especially over high ground. Temperatures are uncertain during this period although current indications are for temperatures to be below normal for the time of year.

Updated: 04:00 (UTC) on Sun 10 Jan 2021

Sunday 24 Jan - Sunday 7 Feb

Confidence for this period is low, though there is a signal for weaker than average westerly winds with Atlantic systems likely to track further south than normal. Therefore, for the north of the UK it is expected to be drier than normal with temperatures around average to a little below. Further south there is an increased chance of unsettled conditions, with above average precipitation and with temperatures slightly above average. Through this period there is a greater than average chance of cold spells across the UK with the associated risk of wintry hazards. There is potential at times for significant snowfall on the boundary between milder and colder air masses, with greatest risk across central and northern areas.

Martin

No, Stav Danaos 

https://www.bbc.co.uk/weather/eh10

9C and sleet this afternoon in Edinburgh today according to the BBC.

I have noticed even the Meto video forecasts for this week are not showing temperature or any detail for Thursday and Friday. When a cold spell looks possible it tends to be hints in the BBC/Meto forecasts that let you know what the thinking is. Also now we have twitter.

Saturday 16 Jan - Monday 25 Jan

Unsettled conditions are looking to transfer across from the Atlantic over the weekend, likely starting on Saturday but, if the system stalls, may occur later. This will bring spells of rain to many areas, these perhaps accompanied by strong winds at times, with drier and clearer interludes between them. The heaviest and most prolonged periods of rainfall are likely to affect the south and west, with the best of any drier conditions more likely in the north and east. Some snow is also likely at times in the north, especially over high ground. Temperatures are uncertain during this period although current indications are for temperatures to be below normal for the time of year, especially in the north.

Sunday 24 Jan - Sunday 7 Feb

Confidence for this period is low, though there is a signal for weaker than average westerly winds with Atlantic systems likely to track further south than normal. Therefore, for the north of the UK it is expected to be drier than normal with temperatures around average to a little below. Further south there is an increased chance of unsettled conditions, with above average precipitation and with temperatures slightly above average. Through this period there is a greater than average chance of cold spells across the UK with the associated risk of wintry hazards. There is potential at times for significant snowfall on the boundary between milder and colder air masses, with greatest risk across central and northern areas.

https://www.metoffice.gov.uk/

Meto not really buying into the cold spell yet.

I think it's fair to say they're being cautious about things but their comments do suggest a decent chance of cold and snow for the North. 

Down South they're understandably not putting much emphasis on cold because when you look at the ens from the various models they're suggesting a reasonable chance of the south in particular being unsettled and milder, albeit still with some colder incursions at times as backed up by "Through this period there is a greater than average chance of cold spells across the UK with the associated risk of wintry hazards. There is potential at times for significant snowfall on the boundary between milder and colder air masses, with greatest risk across central and northern areas."

If the ens start to more uniformly show colder air making it to the South and staying in place for a few days I'd expect the emphasis in the text to change but as it stands it seems a sensible enough forecast given the uncertainties in the output.