Thursday 31st December 2020

Staying cold.

What? Yes, I am writing a weather forecast. Yes, I know it is New Year’s Eve. I haven’t got anything else to do. Have you?!

Oh what a year. The heatwave in summer, the 3rd hottest day ever recorded, the long and glorious spring (even if I did spend it enviously watching furloughed neighbours sunbathing whilst I carried on working). The never-ending rain in February, that soaking weekend in October and now the coldest December in years. Oh and all the thunderstorms that miraculously missed where I live.

What was your highlight? I think I’d go for the long, glorious spring myself.

Still no wintry photographs…thanks to Zara for this one.

We still have pretty crazy synoptics with the polar vortex disorganised and on the other side of the hemisphere from us – yet still very marginal when it comes to whether it will rain or snow. But mostly dry for a few days so I don’t have to worry about being too wrong about rain/snow until next week.

Though don’t be surprised if there is a short-notice wintry surprise that isn’t in my forecast – things tend to pop up at short

Tonight will see some clear spells, some cloud at times and there will be a frost. Down to around -3’C, colder in more sheltered spots. A small chance of fog forming.

Friday may start bright, it may start foggy – but either way it will soon become just cloudy and dull. A small chance of a shower in the afternoon, more likely rain or sleet – but snow is possible. Cold, 3’C. Cloudy overnight and staying a little above zero – but a frost possible around dawn as cloud clears south.

Saturday starts with early cloud, this should clear to sunny spells but the timing of this is uncertain. Cloud will bubble up at times, the odd stray wintry shower is possible but unlikely. Still cold, 4’C at a push but does depend on a bit of sunshine. Some clear spells overnight with a frost, but some cloud at times also, especially towards dawn. Down to around -1’C, but could be a couple of degrees either way if more/less cloud.

Sunday sees an easterly wind set in – an easterly wind in early January surely means colder, right?

Well, almost always an easterly in January would make it colder, but this will have origins from the south-east Mediterranean and be crossing a warmer than normal North Sea. So it will be slightly less cold – but don’t get excited, it will feel colder with a fairly biting wind chill.

So Sunday looks rather cloudy. A bit of sunshine at times and a few scattered showers in the easterly wind. They should be of rain, but I wouldn’t rule out something wintry. Around 5’C but feeling colder due to the breeze. Similar overnight, but dropping to around 1’C and showers more likely sleet or wet snow.

Monday will be cloudy, the easterly wind will be stronger and it looks like some more general showery fairly light rain will spread across from the east. 4’C but feeling much colder. Similar overnight, a tad colder, and showers should still be rain but more questionable – I wouldn’t rule out something wintry.

Tuesday remains mostly cloudy and cold in the easterly wind. A bit more brightness and probably less showers – those that get through should be fairly light also – oh and probably rain. 4’C. Cold and windy overnight, a frost possible and still one or two showers around – perhaps more likely to be sleet or snow.

Wednesday – similar to Monday and Tuesday.

From Thursday onwards it stays cold and probably gets a bit colder. Otherwise details uncertain.

Yeah, I’ve had enough.

Sudden stratospheric warming event is happening by the way. It is on and should be official by 5th January. Still to be determined what form it takes, and then how it affects us down here in the troposphere.

We should see major impacts on our weather by the end of January – it is not a guarantee of a significant cold spell – but gives around a 65% chance. We had one prior to the very cold March in 2013, we had one prior to the Beast From The East in 2018. We also had one in January 2019 – nothing happened. Well, we had that warmest ever February spell…which may or may not have been related to the SSW.

Which leaves me to wish you a…new year. We will get a new year. I’m not setting any other expectations. I just hope for some exciting weather.

I’m already dreaming of that first warm spring day where I can sit in my front garden with my shorts on, having a beer. And please, a decent thunderstorm in 2021 – after some snow. Oh my word, how about thundersnow? That would be amazing for 2021. Yeah, I’m already wishing for too much…it might not even snow despite the best mid-winter synoptics for years.…

Monday 28th December 2020

We are at the beginning of a cold spell, and it could potentially be a memorable spell. Though I tend to find that cold spells only tend to become memorable when there is snow involved. And there are several chances of snow this week – but only chances, all of them far from guaranteed.

This will be a difficult forecast, though as the cold weather itself was forecasted weeks in advance, the details in terms of snow possibilities will be really tricky – and close to nowcasting events.

Two main difficulties – exactly where small features bringing potential snow (or rain) will track, and as I just alluded to, whether precipitation does fall as rain, sleet, snow or a mixture – things are very marginal in terms of temperatures, dew points, etc – and will remain so this week. Though perhaps colder next week, but more on next week later.

Thanks to Lisa for the wintry photograph.

Tonight will be mostly cloudy, a bit of mist or patchy fog possible but most will avoid this, and a slight frost in places by dawn, around 0’C or just under.

For Tuesday we are in this cold northerly flow with low pressure close to our east.

It will be mostly cloudy – one or two scattered wintry showers during early morning, around a 30% chance of catching one, then another cluster of wintry showers heading down from the north in the afternoon – though these look more likely to be to our west as things stand. A little brightness at times, and catch a morning shower and there could be a temporary slight covering of snow. Cold and breezy, 4’C. Clear spells overnight, though some cloud later in the night – down to around -1’C and frosty for most.

Wednesday morning will be cold with hazy sunshine. An area of rain with snow on its northern flank will slip down from the north-west in the afternoon – the exact track is very uncertain, but if we are on the northern edge there should be some snow falling – this is currently the slightly more likely outcome. Even if it is a bit further north than currently projected, and therefore is rain when it arrives, there is a good chance that it will turn to snow. Either outcome could see 1-5cm of snow accumulating.

If it is quite a bit further north than currently projected, then it will be rain – it could also be further south (second most likely of the four outcomes) and we remain dry but cold.

Around 4’C by day and -2’C overnight. Ice possible.

So Wednesday’s potential snow was barely showing on the models yesterday – we are looking at 48 to 72 timeframes in terms of developing features so uncertainty really is high from Thursday onwards, in terms of potential snow.

New Year’s Eve remains cold, if anything colder – especially if there is snow on the ground. Sunny spells, cloud at times (especially afternoon), the odd scattered wintry shower. 3’C and breezy. There are suggestions of an area of snow spreading down from the north or north-east either evening or overnight, but this is just an early suggestion. Around 0’C overnight if snowing – or down to around -3’C if clear. Ice very possible.

New Year’s Day remains cold with sunny spells and chances of wintry showers – though lower chances than previous days as it currently stands. 3’C, though perhaps a tad lower if there is lying snow. Uncertain overnight – either cloudy with a bit of rain/snow or frosty.

Saturday is still cold – I hope you will be getting used to it at this point. A fairly slack NNE flow with high pressure fairly close to the west.

Details uncertain, but arguably more likely dry than not, and around 4’C.

Sunday similar, though a slightly increased chance of wintry showers. It remains cold – whatever!

Next week will be cold, perhaps verging on the very cold – though I guess the definition between cold and very cold is woolly, I don’t have a strict definition in mind – maybe 0’C by day would be very cold?

The most likely evolution is for either an easterly or north-easterly, and further snow showers or spells of general snow would be likely at times. I cannot rule out rain instead, but snow more likely.

A somewhat less likely evolution would see high pressure close to or over the UK, bringing cold, settled conditions – with harsh overnight frosts and freezing fog possible.

Where do we go from here?

Well I forecasted the cold spell for the end of December, and to last into the very first part of January, as part of my winter weather forecast that I wrote at the beginning of December. I then expected a return to mild and wet conditions.

I am now doubtful as to whether we will return to mild and wet conditions in January – the tropospheric polar vortex that brings our mild and wet winters is completely disrupted, the Atlantic jetstream is far to our south, La Niña and other background signals still favour a continuation of the cold too – if anything background signals favour an intensification of the cold in January.

And this is before the sudden stratospheric warming (SSW) event that is now likely, somewhere between 5th and 12th January, which would give a good chance of a significant cold spell to follow, normally starting within 2-4 weeks of the SSW event, though I’ve seen some people more knowledgeable than me suggesting that lead time would be even shorter.

I do expect an attempt to assert milder conditions from the south-west during January. The earliest possible attempt would be around 7th January – unlikely but possible. I’d suggest the attempt more likely in the period between 10th January to 14th January, but any attempt at mild conditions from low pressure bumping into cold weather would at least start with heavy snow.

And even if mild does win for a while, I fully expect further cold conditions to return either late January or into February, assuming the SSW falls in our favour for cold.

I don’t want to get ahead of myself – there are plenty of snow chances ahead, not just this week but in the week or two that follows, and if none of them actually happen you’ll be wondering what I was on about – and perhaps just think it was a bit colder than normal.

But there certainly is now a chance that this could be one of those more memorable winters.…

Monday 28th December 2020 – Rain/Snow Update

So the thin band of rain, sleet and snow is to our west, lying north to south. It is starting to pivot so will be laying more diagonally across the country by late morning, and our area should be involved, most likely a little later this morning and through to early afternoon – by late afternoon the thin band of rain, sleet and snow should be to our south, lying west to east.

Some places under the weather front are reporting rain, others wet snow, so precipitation type is just an educated guess, I’d suggest rain is most likely for now, especially if the precipitation is light, but towards lunchtime if the rain becomes heavier, it should more readily turn to sleet or wet snow.

I could easily be wrong though!

Also it is showery in nature. Full update later…not sure when I’ll do it.…

Thursday 24th December 2020

So it’s Christmas Eve and it is actually cold. What a strange year this has been – a cold spell near Christmas, how unusual. And this cold spell will last into the start of January too.

Quite an unusual winter set-up and it has been for a while. Most winters we have a well-organised polar vortex, generally close to Greenland, with a strong jetstream bringing lots of low pressure systems from west to east.

This December we have a very disorganised polar vortex, with the strongest part and strongest ribbon of jetstream on the opposite side of the earth to us. The Atlantic is quiet – blocked with high pressure reaching into Greenland.

And this means that we now have a northerly flow, and this will be set in for a couple of weeks. No deep cold close enough to our north to tap into, so things cold but marginal in terms of snow, at least for us in lowland southern Britain.

I would be surprised if we don’t see snow falling at some point in this cold spell, and significant, disruptive snowfall is within the realms of possibility – but won’t be forecasted until closer to the time. I think I can forecast 4 days tops at the moment in terms of details. After that is just general theme (cold) and potential frost/fog/snow/sleet/rain.

Rather a long introduction – I don’t have any new photographs but I don’t think I’ve used this one from Paul yet. With a bit of luck, I might have some more seasonal photographs for next week’s forecasts.

So today will be cold in the northerly wind. Sunny spells, especially this morning, more cloud this afternoon but still some sunshine. A very small chance of a shower afternoon/evening, which could be wintry – but only a very small chance. 5’C at best. Wind fading overnight, fairly clear with a frost, down to around -2’C.

Christmas Day will be sunny but cold. Becoming a bit hazy in the afternoon but still bright. 4’C. Down to around -1’C at first in the evening, but temperatures ticking up gradually overnight as cloud thickens and the wind picks up, 5’C by dawn.

Boxing Day will be mostly cloudy and windy, with bits of occasional light (ish) rain – though dry much of the time. A little brightness at times also, and around 9’C. Wind continuing to strengthen overnight – gusts of over 50mph could cause some isolated damage. Rain becoming persistent and heavy too.

Sunday starts with heavy rain and strong winds – a bit of uncertainty over when this will clear, any time from 6am to midday. There is the potential for a squall line on the back edge, bringing a brief spell of very heavy rain, squally winds – possible hail/thunder also – the squall line element uncertain at this stage. Once this clears we’ll be looking at sunny spells and a small chance of a shower – which should still be of rain, if you catch one. 6’C but feeling colder. Frost possibly overnight, but this depends on the position of weather fronts.

And that is where my ability to provide details ends. So short, I know.

The general picture then is low pressure sat over the UK, with fairly cold air having filtered down from the north.

Weather fronts will move around the edge of the low, bringing a risk of more persistent rain, sleet or snow – but where they will be and when is impossible to know at this stage.

Other features will develop within the flow, bringing wintry showers too – but again this is too far out. I think we won’t know until around 24-48 hours before any particular day, what the chance of rain/sleet/snow is.

Until then, it is just potential.

Certainly it will be cold. Temperatures broadly in the range of 2’C to 6’C by day, with overnight frosts on the nights when we have clear skies.

Should we get a notable snowfall that settles, then this will reduce expected temperatures, and therefore feedback into an increased chance of further snow as the cold spell progresses. Freezing fog will also be possible – which could also mean daytime temperatures close to 0’C should this occur.

As I said earlier, I will be surprised if we don’t see snow falling at some point in this cold spell.

Right, I’m off to go enjoy the completion of my self-isolation period and buy some bread. And possibly wine.

I wish you all a Merry (ish) Christmas, or if you don’t celebrate Christmas then I wish you a pleasant extended weekend.

Next full forecast will be on Monday, but I’ll update you before then on any wintry potential when it becomes clearer…if it does!…

Wednesday 23rd December 2020 – Rain Update

Morning. So rain is developing and spreading north at the moment, it is showery – some of it is heavy.

By mid-afternoon, the heaviest and most persistent rain should have cleared to our north temporarily – still some uncertainty but I’m expecting it to stall roughly 20-50 miles north of our location – and where it stalls the rain likely becoming very heavy, for those locations they could easily get 40-50mm of rain.

For us, the most likely outcome is a total of around 10-20mm of rain, a fair amount but shouldn’t be problematic, assuming the rain band does clear north in mid-afternoon as I describe and expect.

It then sinks bath south in the evening and overnight, bringing further rain, before fading.

Full forecast will be tomorrow morning, but briefly:

Christmas Eve cold but sunny at times, especially in the morning. Small chance of a wintry shower. 4’C. Frost overnight.

Christmas Day, cold with sunny spells, 4’C. Cloudy overnight – no frost.

Boxing Day cloudy, windy, a tad milder (ish) with occasional bits of rain. Heavy rain spreading down from the north with gales overnight.

Sunday, early heavy rain and strong winds clearing to colder weather with showers – probably not wintry at this point. Possibility that as the morning rain clears (unknown time – could be anywhere between 3am and midday really) that there will be a squall line, with a brief spell of torrential rain, thunder, hail and very strong gusts of wind, possibly mixed in.

Monday onwards, cold with snow chances. Cold spell pretty much nailed on for 7-10 days, perhaps longer. A good chance of snow falling at some point during this period – but very uncertain at this stage – could easily fall as rain in our location, or a mix or rain and snow. But likewise, we could see a decent dumping of snow at some point. Way too early for anything other than “potential”.

I am certainly forecasting some very difficult weather forecasting.

I’ll be back with a full forecast tomorrow morning…didn’t intend on writing this much but lots going on at the moment!…

Monday 21st December 2020

Well I hoped you all got through that emotional roller-coaster of a weekend intact. And the weather is going on a bit of a roller-coaster this week – mild and wet at first, then cold, sunny and frosty – with a northerly plunge after Christmas. Snow possible.

Thanks to Jade for the photograph – though only the bottom half is representing the next few days.

This evening sees some showery rain – the odd heavy burst possible. Remaining cloudy overnight, still the odd shower and some drizzle, around 10’C.

Tuesday morning should see some brightness, though the odd splash of light rain around. Generally cloudier in the afternoon with patchy rain becoming more extensive – not especially heavy and still rather showery. Around 10’C. Cloudy with occasional showery rain overnight, 11’C.

Wednesday is when things start to become interesting with low pressure approaching from the south-west and deepening over us – with a large area of high pressure to the west blocking the Atlantic.

Spells of heavy rain will push up from the south and the rain band will stall somewhere across the south/central UK and intensify – becoming very heavy. The peak could be around the M4 kind of area, or perhaps a bit further north over the Midlands – which could mean the difference between 20mm of rain (a fair amount) or something closer to 40mm which would cause localised flooding issues.

The rain then clears south-east overnight, with winds becoming strong too. Mild during the day at around 13’C but slowly cooling down later and overnight – 4’C by dawn. There is a very, very small chance of some back-edge sleet/wet-snow as the rain clears overnight, but a very, very small chance.

So Christmas Eve (also my freedom from self-isolation day…yeah I received the dreaded notification) sees a northerly wind.

Any early cloud will quickly clear to be replaced by sunshine – but cold in the fresh northerly wind at 4’C. There is around a 25% chance of a shower or two in the flow, they could be of rain – or sleet/snow. Clear and frosty overnight, down to around -2’C.

Christmas Day will be fairly sunny but cold. Some cloud around and the wind will be lighter but still a notable northerly breeze. We should squeeze 4’C. Frosty at first in the evening, down to around 0’C but picking up as cloud thickens during the night, ending up around 4’C.

Boxing Day looks mostly cloudy, windy with some occasional bits of rain – though mostly on the light side. A temporarily milder flow from the west, around 8’C. Rain becoming more persistent and heavy in the evening – perhaps very heavy for a spell overnight. Around 6’C.

Sunday sets the scene for the next few days – low pressure having moved down from the north bringing cold air with it, and hanging around the UK for a few days. Not entirely dissimilar to early this month – except this time temperatures are lower and snow could fall at times – though still very marginal for the south of the UK as to whether it will be rain, sleet or snow, and very easily we could see varying precipitation types during this period.

Details very much subject to change from here, but currently Sunday looks dry with some sunny spells – a small chance of a shower. Around 5’C. Frosty overnight, down to around -3’C with freezing fog possible.

Monday will be colder, with maximum temperatures around 3’C. Suggestions of an area of rain/snow moving down from the north, but track is uncertain let alone whether it will be rain or snow.

In fact it is impossible to give details any further.

It will stay cold. Daytime maximums between 2’C and 5’C, with overnight frosts likely – unless there is cloud cover.

There is a good chance of snow falling at some point. Settling? Well, less confident on that matter. As I mentioned earlier, at times is could be rain, at times snow – maybe it will all be snow – but maybe it will all be rain.

It is far too marginal a call right now, a week away. But it certainly looks more seasonal than it has in years.

The cold weather is likely to stay for the first part of January, roughly first week. Mild and wet is likely to replace it with a more south-westerly flow, but cold blocks can take a bit of breaking down.

Looking further ahead – and further up, regular readers will know that I look for sudden stratospheric warming events during winter, which happen roughly every other winter, and give a good chance of significant cold spells within 2-4 weeks of an event. The Beast From The East in 2018 was a classic example.

I thought that there was a good chance of one this winter, and one is now being modelled for the beginning of January. No guarantee that it will happen, but stratospheric forecasting is more stable than our chaos down here.

And if it does happen – there is no guarantee that it will be strong enough to split the polar vortex (which is what cold/snow fans want), and then that the pieces fall in the correct places. But it looks promising – so that would mean a good chance of a significant cold spell during February, or perhaps even from late January.

We shall see. This winter is looking very different from recent winters…and yes I am still talking about the weather.

I will ignore any Christmas wishes tonight! As I will be back on Christmas Eve for definite…I will sadly still be in London. Which at least means you get a full forecast, probably in the morning though. I should join a Zoom call with the folks in the evening, even if I cannot sit next to my parent’s Christmas tree and slowly pick the needles off.

I wish you a pleasant few pre-Christmas days…and if you are prone to winter flooding then maybe keep an eye out on the usual websites like the Environment Agency. And keep a carrot handy in case you have the opportunity after Christmas to build a snowman.…

Thursday 17th December 2020

Mild and wet for a few days – but turning colder in time for Christmas – Christmas Eve, in fact. Even the Met Office finally seem to be buying into cold weather for the end of the month.

Still a lot of details up in the air for the Christmas period, I still rate the chance of a technical White Christmas here as very, very small – 10% at the very most. More later…first we need to talk rain.

Thanks to Naomi and Gary for the photograph. Not very representative of the coming weather – but too good not to use!

Tonight will be cloudy with a band of showery rain crossing after midnight. Around 8’C at first, but picking up to 11’C as the night goes on – and becoming windy also.

Friday will be mostly cloudy with occasional bits of rain – mostly light. Mild and windy, becoming notably strong later in the day, 12’C. A band of rain slowly crossing overnight, some heavy rain probably mixed in. Winds becoming less strong, 10’C.

Saturday sees low pressure to our north-west – and things not so blocked to our east as they have been the last few weeks.

Early cloud and rain will clear east to be replaced by sunny spells and variable amounts of cloud. Some heavy showers may push inland in fairly strong winds, 11’C. Clear spells overnight – it should be dry but a passing shower cannot be ruled out. Down to around 6’C.

Sunday sees sunny spells and lighter winds. Variable amounts of cloud and one or two showers possible. 10’C. Clear spells at first overnight and quite chilly – heavy rain arriving from the south-west later in the night, with strong winds possible. Down to around 5’C overnight, picking up to around 11’C as the rain sets in.

So Christmas week starts with a small succession of low pressure systems arriving from the south-west, and I don’t feel the modelling is quite there yet – so there might be some differences in timing, rain/wind intensity, from what is currently expected. I guess I cannot totally rule out the low pressure systems being further south than currently modelled, with colder air and perhaps some sleet/wet snow mixed in – but I think very unlikely for the start of the week.

Wet and windy to start Monday – clearing to sunny spells. Mild, 13’C. Uncertain overnight – further rain could spread from the south-west but it is uncertain how far north it will get – and therefore temperatures could be anywhere from 3’C to 12’C – the boundary between cold and mild being rather small.

Tuesday is probably rather cloudy and dry – awaiting Wednesday’s low pressure system. We should stay in the milder air, somewhere between 8’C and 12’C. Further heavy rain likely spreads up overnight – and likely at the upper end of the mild bracket.

Wednesday looks wet at times – uncertain as to when, but some heavy rain is likely at times with milder air, say 13’C. Winds could become strong as the system develops. The wind then turns to the north later in the day as the low pressure system really winds up and pushes east – strong winds possible overnight as is heavy rain. I cannot rule out the rain turning to sleet or wet snow. Plenty of uncertainty this far out so expect details to change a bit.

Christmas Eve starts with a fairly strong northerly wind – it could still be wet, depending on the timing of Wednesday’s system. Likely becoming sunny but feeling cold, 6’C at best. I cannot totally rule out a shower. Likely frosty overnight, down to 0’C or lower.

Christmas Day looks cold with sunny spells. Around 4’C. A shower is possible – and could be wintry. But a low chance of both a shower, and it being wintry.

Boxing Day is pushing things a bit too much – suggestions of a more north-westerly flow so temperatures ticking back up a little. Uncertain on sunshine/cloud/rain etc.

Where we go from there is more uncertain, though I’d suggest a northerly flow (or something close to) is the slightly most likely outcome for the final week of 2020 – which could easily bring some snow showers. Alternatively something cold and dry would be a very possible outcome.

Not especially expecting a return to wet and mild just yet, and we may even get a chilly start to January too. I still expect a reversion to wet and mild for January, but maybe not until the second week now.

Lots going on, I’ll try to keep you updated if anything major changes for next week, in the weekend model runs. Though I have lots going on myself (albeit only inside my house, alas).

Full forecast will be on Monday as usual…probably just a short update on Christmas Eve though…we’ll see.…

Monday 14th December 2020

So, milder with rain at times for the next week or so. But a change to colder conditions is currently the favourite for around Christmas…oooh!

Thanks to Paul for the photograph.

This evening sees a few scattered heavy showers, clear spells overnight though the odd stray shower still possible, down to around 5’C.

Tuesday sees sunny spells and variable amounts of cloud. One or two showers may push this far inland from the south-west. Milder, 11’C and breezy. Cloud thickening overnight and becoming quite windy, 8’C.

Wednesday starts cloudy, though the cloud perhaps thin enough for some hazy sunshine in the morning. A band of rain will push east slowly during the afternoon – several hours of rain and quite heavy. 10’C, maybe 11’C. Rain clearing during the evening, clear spells overnight though a chance of a heavy shower also, down to around 5’C.

Thursday will be sunny and breezy. Some high cloud building as the afternoon goes on. 10’C. Cloudy overnight with some showery rain, mild with strong winds also, 11’C.

Friday will be cloudy with strong winds – but mild. Some showery bits of rain possible in the morning, with further heavy rain likely either afternoon or evening (or possibly both). Close to 13’C. Further outbreaks of rain likely overnight, a bit less windy, 11’C.

Saturday may start wet – uncertain quite when the overnight rain will clear. Sunny spells with the odd scattered shower should follow. Still quite windy and mild, 11’C.

Sunday probably seeing sunny spells and somewhat cooler conditions – but confidence not especially high.

Next week then sees a battle between milder air to the south-west trying to spread up, and colder weather to the north trying to filter down. The cold air winning out is currently the favourite, around a 60% chance though greater uncertainty on the timing of its victory.

Slight favourite would see milder air temporarily winning for Monday and Tuesday, perhaps Wednesday – with further heavy rain and strong winds at times.

And then for Christmas Eve or Christmas Day colder air could be arriving. Yes, this means that there is a very small chance of a white Christmas, 10% chance at most. I’d suggest a somewhat less small chance of seeing snow falling after Christmas Day.

Any more details on the potential cold spell, including how long for, when it starts, when it ends – whether it will be dry and frosty, or if there is a chance of wintry showers, is all currently uncertain.

This is a long-signalled window of opportunity for a cold spell roughly between Christmas and New Year, perhaps into the first few days of 2021. It’s around a 60% chance – mild and wet could still win out which is our usual prevailing weather for December.

I still expect January to be mostly mild – wet and windy quite often too.…

Thursday 10th December 2020

So we’ve had our cold spell, now time for something a bit milder, but with some rain at times too.

The general picture still has the high pressure block out to our east, but low pressure systems from the Atlantic are now making it as far as the UK – though not able to progress any further east.

Thanks to Paul for the photograph.

Tonight sees rain spreading from the west, from around 10pm until 4am. Down to around 6’C.

Friday will see a fair amount of cloud around but there will be some sunny spells, especially in the afternoon. The odd lightish shower around. Milder, 10’C. Cloudy overnight, some patchy fog may develop, also the odd spot of rain possible by dawn, 6’C.

Saturday starts cloudy – a bit of occasional light rain but nothing notable. Sunny spells will follow for the afternoon, and scraping around 8’C. Clear spells for a time overnight, a frost in places, getting down to 0’C. Becoming cloudier and windier by dawn.

For Sunday we have a big area of low pressure close to the west driving our weather.

The morning sees more showery rain, some light, some quite heavy bursts – a brief dry (ish) spell follows, before further more persistent and probably heavy rain arrives, either late afternoon or evening. Some fairly strong winds, and becoming gradually milder – reaching around 12’C by midnight. Showers still possible overnight though the main rain will have cleared.

Monday sees sunny spells, variable cloud, one or two showers pushed inland in the wind. Still on the mild side, around 11’C. Variable cloud overnight, 8’C.

For Tuesday we are still in the circulation of the low pressure out west, that is unable to move through.

It should be fine with sunny spells, though still breezy. Though certainly possible that an area of showers could develop and head our way. Around 10’C.

Wednesday is more likely to see an area of wind and rain push up from the south-west – a cut-off low from the main circulation of low pressure stuck to our west. Details uncertain – it may even arrive on Tuesday night, and may stay to our west – though at the moment the most likely outcome is tracking over us during Wednesday to bring some wind and rain. Still around 10’C.

By Thursday uncertainty increases, but I’d suggest something similar to Tuesday is most likely – sunny spells, breezy with a chance of an area of showers pushing through.

Friday and into next weekend likely see low pressure pushing over the UK, making a bit more progress east – so expect more in the way of wind and rain. Though a small chance in stead of something colder and drier developing.

I still think there is a half-decent chance of a notable cold spell somewhere in the period of the last 10 days of December and first few days of January.

Mild and wet is always the prevalent pattern here in the UK in winter, and it always needs most of the jigsaw pieces to come together to deliver a decent cold spell – and we only have a couple of pieces at the moment. But this time last year, the jigsaw had been shredded with the pieces thrown off a cliff.

Once this window of opportunity goes, then I expect it generally mild for a few weeks, with wind and rain at times, and perhaps into the beginning of February also – sudden stratospheric warming events depending.

I wish you all a good weekend – I’m actually going out twice. Though the last two times this year I expect…especially given that I live in London.…