January 5th, 2026 !

Hi All,

Well, what a start to the year, meteorologically and politically I guess, a brave new world ? I don't think so, but I better not go there in this blog. So as I type this, dawn is breaking and the birds are already queuing up to be fed and watered. Tough times for them at this time of year with this weather. Colder weather definitely makes birdlife bolder as they forage for food. Out on a beautiful winter walk at Fineshade's Wood, I paused to take the photograph below and next to me a bird landed within touching distance. The other half noticed it (I have to say this). It was Britain's smallest bird, a Goldcrest and for the next 5 minutes it flitted amongst the foliage within feet of me, looking for insects and seeds within Old Man's Beard flowers, shown below festively topped with snow.

I didn't realise, but Old Man's Beard latin name is Clematis vitalba and I think it is the UK's only native Clematis species. To some it is an invasive weed, but to birds, it's flowers are a source of seeds and insects, especially in the winter. It is also known as 'Travellers Joy' because it tended to grow along well-trodden tracks and paths in the past, you can read about it here

The present run of weather is quite unusual given our run of mild January's, this day a year ago air temperatures were nudging into the low teens as we picked up a mild south westerly airstream. Today it will not break zero in a lot of locations.

Overnight here, we got down to -5.7°C, as that cold, Arctic air arrived over Christmas and took air temperatures down to what used to be a 'normal' range for this time of year. Clicking on Silkeborg Golf Club's, Davis weather station in Jylland, Denmark, I can see they are currently at -15.0°C after dropping to -15.7°C overnight. (I hope you and your team have your thermals on Jeppe !!!😮)

Earlier in December, I talked about an early Sudden Stratospheric Warming event that took place at the end of November, early December and its potential to upset the west-east flow of the jet stream. Well that shook out over Christmas as we lost that strong westerly airflow, leaving the stage set for colder air from the east and north to influence. These are precisely the same conditions that gave us the cold winters of 2010 and 2013. The big question I guess you're now all wondering is how long it will persist for ?

That's a tricky one to answer because later this week we have milder, wetter air trying to push in and colder air sitting over the U.K. For some it'll be rain, but further east this may turn to snow.

ECMWF MLSP and Precipitation projections courtesy of tropicaltidbits.com

General Weather Situation

So, the first event this week takes place on Tuesday / Wednesday when a subtle low pressure system idles down the east side of the country. Its position is in the North Sea, so the U.K will get the trailing edge of the low pressure which means northerly winds. For this reason I'd anticipate that this event could bring further snow, especially for the east side of the country. For Denmark, you'll get the leading edge of the low pressure, which means southerly winds, but I still think that will mean snow, rather than rain. At the same time as this we will see moisture trying to push in from The Atlantic across Ireland and the south west of England / Wales. I think this will fall as rain as the air temperatures associated with this rain will be warmer. Now this rain will move eastwards and butt up against the colder air inland. So there's an additional chance of this turning to snow as it does so. Quite where the demarcation line will be is anyone's guess.

Next up during Thursday and Friday we have another low pressure system. This one pushes up from the south and will I think primarily affect the southern half of the U.K overnight into Friday. I'd draw a line across from the M4 as a starter. Since this low originated in the south it will again bring some milder air with it and again pose a threat of that rain turning to snow (and maybe heavy snow to boot) along its northerly edge. This low pressure will then track across into Germany where I think it'll bring heavy snow there and easterly winds to Denmark, though the moisture associated with the low doesn't (at this stage) look to threaten Denmark itself. It will though drag in snow showers to Denmark over the weekend on a biting easterly wind. Back home during Saturday pm we have more rain pushing into Ireland from the west with some really closely-packed isobars. This means wet, windy and I think milder air as well for all areas. So we may see this fall as snow initially before it turns to rain during Sunday across the U.K. This same system will then push into Denmark for the start of next week and again it'll butt up against that cold air. It could fall as rain, sleet, snow or frozen rain.

Starting next week, we see things settle down a bit for the southern half of the U.K and Ireland, but a nearby northern low will keep it unsettled and colder for the north of the country. So a north-south divide with milder temperatures maybe 6-7°C for the south and colder air for Scotland and the north of England. As it looks now, a ridge of high pressure will then push in later next week and that'll bring more settled conditions and maintain those temperatures in the high single figures. Now a lot can change between now and then and there's a lot of variability in the updates, so that cold air may or may not make a return, we will see....

Agronomic Notes

Now there's only one subject to discuss when we have a set of weather conditions like the above i.e Frozen ground and the potential for mild air and rainfall following on.

It creates a tricky dynamic for greenkeepers and ground staff alike. On the latter, I know this Christmas and New Year period has been particularly hard work (one way of putting it) where a run of fixtures for football and rugby has meant groundsmen and women battling with frozen pitches, frozen covers and the like, to ensure an event goes ahead and surfaces are playable and safe. Obviously I am talking about pitches without lights and undersoil heating. These are the unsung heroes behind many a fixture and worthy of a mention on my part.

Before we talk about the issues related to a potential rapid thaw, it is interesting to consider the temperature dynamic between weather station and forecasting height (typically 2m above the ground) and ground height during periods of hard frosts. I have been aware of the difference between the two for a good while now, indeed I previously fitted some of our Davis weather stations with an additional temperature / humidity sensor at ground height, when I first started work on disease modelling 10 years ago. (cripes!) That said, I was reminded of this dynamic by the ever-sharp, Rob Hay of Northampton County G.C when he brought it to my attention over the holidays, thanks Rob !

What you notice is that the air temperature immediately above the ground dips much faster at dusk (due to the effect of the cold, frozen ground) and drops to a significantly colder temperature overnight during periods of hard frost than the air temperature at 2m above ground. As the ground cools further, the difference grows. As an example, overnight the air temperature @ 2m dropped to 4.8°C, but the air temperature at ground height dropped to -7.1°C.

You can see how the two compare in the graph below ;

Air temperature at ground height vs. 2m - The Oxfordshire, Thame, U.K

So the situation we may see play out over the next few days is milder, wetter air falling onto hard and deep frozen ground. The rain will be much warmer and so as it falls it will start to thaw out the surface, however below this the ground will still be frozen.

You can see this dynamic in the image above with water sitting above a frozen layer sub-surface. The danger is that to the un-initiated eye (and let's face it these are in abundance) the surface is clear and fit to play on. The reality is that you have a very mobile surface layer which under pressure of foot or mechanised traffic will detach from the frozen base layer. The consequences are grave from a health & safety perspective (it's very easy to slip when the upper layer is 'plastic' and break bones) and for the grass plants root system because movement of the upper thawed layer over a frozen deeper layer will shear the root of the grass plant.

I have detailed the exact dynamic in the pdf shown below which can be downloaded here

Now, of course there's a plethora of variables here including depth of frozen layer, rootzone type, (high sand content surfaces tend to thaw quicker as they contain more air) the amount of rainfall falling over a given period (rainfall intensity) and of course air temperature. Gut feeling from the weather maps, I see Ireland had a reasonable frost overnight but temperatures are now above freezing, so it may be less of an issue here (may be / may not). I do envisage it may potentially be an issue for The South West / Wales and south of England in the early part of this week before affecting central and eastern areas later. A situation to keep an eye on for sure.

OK, that's me for the first blog of 2026, I now need to get on with my presentation at BTME 2026 shown above.

I look forward to seeing you all in a couple of weeks time if you attend the talk or come to see myself and Peter Palmer on the Prodata Weather Systems stand 634.

All the best.

Mark Hunt