Schaf going for ‘increasingly likely mild will win out by Sunday’

Mild by Sunday? he said last night that the colder air from the east would win out and stressed the high would evaporate the low pressures?

 

Mild by Sunday? he said last night that the colder air from the east would win out and stressed the high would evaporate the low pressures?

But based on today's model runs he - and/or the Meteogroup chief forecaster - now thinks it's "increasingly likely" that that won't happen. Sadly, I'd have to agree with them. (|Not that I'm any sort of an expert.)

Weather forecasts are predictions of what will probably happen, based on best available information, not what will happen (unless the forecaster is Thor, Osiris* or YHWH), and beyond a couple of days there is increasing uncertainty.  So no surprise that 5 days out they change, as new information becomes available.


* and personally I don't think he's much good

 

But based on today's model runs he - and/or the Meteogroup chief forecaster - now thinks it's "increasingly likely" that that won't happen. Sadly, I'd have to agree with them. (|Not that I'm any sort of an expert.)

True but looking at charts like the 12z GFS - which show temperatures of +0-3c and then back to -1c by 1800 with snow moving in from the SW does make you 'scratch your head'.

 

Mild by Sunday? he said last night that the colder air from the east would win out and stressed the high would evaporate the low pressures?

Models change. So it’s only right that he emphasises the changing probability. 

We have been issued a weather warning for 1 to 2cm of slush. Things are looking up🤣

A lot of uncertainty in the forecast for the weekend still.

This is for London and the southeast:

Outlook for Friday to Sunday:

Likely remaining cold throughout with strengthening southerly winds. Mainly dry and sunny on Friday and Saturday. Possibly turning cloudier on Sunday perhaps with rain and snow later.

MetOffice now have Snow and Ice warnings for Cornwall and Devon for both tomorrow and Friday. 

Monday 15 Feb - Wednesday 24 Feb

Rather cloudy with rain at times into Monday with any snow likely being restricted to the high grounds of Scotland, though there is signal for some widespread snow to low levels plausible. Temperatures remain split, with the northeast seeing around average while feeling milder in the south and west. However, the boundary between these two layers moves slightly north - giving some milder and wetter conditions into central and western areas. Through the rest of next week, conditions look likely to turn milder and wetter than seen recently. The heaviest and most frequent spells of rain and showers are likely in the west, with conditions drier and brighter at times in the east. By next weekend colder and drier conditions may gradually become established once again.

Wednesday 24 Feb - Wednesday 10 Mar

Into late February there is a signal for higher than average pressure to expand westwards leading to an increased chance of snow showers redeveloping in the east, for conditions in the north to become generally quite settled and for unsettled weather in the south, with disruptive snow possible. A similar picture continues into March, though milder conditions in the west look more likely to spread northwards.

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

BBC monthly outlook

Summary

Milder for a time but cold likely to return later

_________________________________

Wednesday 10 February – Sunday 14 February

A bitterly cold and, in places, snowy week ahead

As "the Beast from the East" developed early this week, temperatures plummeted well below average while eastern and central parts of Britain saw heavy snow showers. Further west, although it stayed mostly dry, hard frosts developed overnight.

From midweek and through to mid-February, high pressure is likely to build into the north of the UK and the North Sea, putting an end to the strong easterly winds, but not to the cold.

This large area of high pressure is likely to extend from Scandinavia south through the North Sea and into Central Europe, staying to the east of the UK. Winds will be light and shift south east, which will still bring in some colder than normal air from Germany. However, the biggest difference will be that heavy snow showers from the North Sea will ease.

By the end of the working week and into the weekend, low pressure systems and weather fronts to the west will attempt to get into the UK while high pressure to the east blocks them. We will end up under a battleground of two very different air masses for a few days, but as the high shifts eastwards the milder air will eventually filter through the country. This will bring a risk of a band of snow for many as a milder weather front moves over the colder air from the east.

Monday 15 February – Sunday 21 February

Milder and more unsettled for a while

Through the middle of February our weather (and the weather for all of northern Europe) will be at the mercy of a large area of high pressure, often referred to as a "blocking high". It gets this nickname because it acts as a large road block for incoming low pressure systems from the Atlantic. This means it will tend to be drier and colder for areas influenced by the blocking high.

However, that doesn't look like it will include the UK next week. We are right on the edge of the high, which is expected to take up residence in the Baltic Sea and Germany, but it looks like it will be just far enough away that will be see Atlantic weather fronts move in from the west and south west.

This means that, at least for next week, we are likely to get a break from the cold. The weather fronts will be moving into the UK from the Azores, dragging sub-tropical Atlantic air with them. Temperatures will go from bitterly cold in places this week, to several degrees above average next week, making for quite a change. This will come with wetter and windier conditions too, these most frequent in southern and western areas.

Our forecast is very sensitive to the exact strength and position of the high, and some minor shifts could see the blocked pattern move over us. If the high is a bit further east, weather fronts will tend to be stronger and more frequent, leading to an even windier and wetter outlook. If we do get some cold filter back in from the east, it is likely to hit only eastern areas and not be nearly as frigid as we have experienced in recent days.

Monday 22 February – Sunday 7 March

Cold patterns return and may linger into March

Towards the end of February and into the first week of March, the forecast becomes trickier to pin down. There are a lot of signals from teleconnections (large-scale atmospheric patterns that can influence UK weather from afar) that we may see a return of a colder, drier pattern as high pressure edges back into northern Europe.

One such pattern is called the Arctic Oscillation, or AO for short, and it is currently strongly negative. This means that there is higher pressure than normal over the Arctic ice cap. Historically, when this pattern has occurred in January and early February, it continues to dominate through to early March.

High pressure north of the UK leads to a colder pattern for North Europe, but also a lot of drier than normal weather too with some crisp, sunny afternoons.
In addition, "La Nina" is currently cooling the water in the equatorial East Pacific, and this tends to favour more frequent Atlantic weather fronts for the UK. This signal is mostly being overpowered by the Arctic Oscillation but should begin to dominate later in March.

Computer model skill at this range for this particular pattern is expected to be rather poor, so we are leaning more on historical precedents which can prove quite useful for our long-range forecasts. However, it does mean confidence is rather low as well, and there is a risk that high pressure will weaken enough to allow Atlantic weather systems to dominate (as La Nina favours). If this pattern pans out, it will be milder, wetter, and windier (more like a typical late-winter/early-spring for the UK).

In short, cold and dry weather is expected to return and persist into March as Arctic high pressure dominates our weather patterns.

Further ahead

Peering ahead into mid-March we will see if there are better signals for a return of weather fronts and an end to the cold, dry winter.

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

Interesting article from the Dutch Met Office on the increasing rarity of severe cold: Dit bedoelen we met strenge en zeer strenge vorst (weeronline.nl)

In Dutch but very readable using auto translate.

Interesting, both long rangers going for cold again with snow.

BBC seems to be going for cold but dry weather returning. Met Office still mention the chance of disruptive snow, primarily further south. Personally, I don't think long term text forecasts will be reliable over the next few weeks. 

STV weather just now, Sean Batty saying big thaw at the weekend, temps up to 9c in Glasgow on Monday

Monday 15 Feb - Wednesday 24 Feb

Rather cloudy with rain at times into Monday with any snow likely being restricted to the high grounds of Scotland, though there is signal for some widespread snow to low levels plausible.

<snip>

You would hope that whoever was entrusted with writing the outlook would have better English skills than that. I think I can work out what they are trying to say, but it's a struggle.