DEW
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17 January 2021 07:35:04

FAX and BBC week  ahead bringing LP up from the SW across the UK to sit off the NE of Scotland by Thu 21st with N-lies setting but lots of wet weather before then


GFS arrives at the same position though less of the LP keeps to the W of the UK en route; although the LP off Scotland on 21st intensifies for a day or two, it then fills and brings in SW-lies until Thu 28th when there's a re-run, brief N-lies and SW-lies to follow. After that there's a mobile westerly pattern with depressions and ridges of HP following on each other through to Tue 2nd.


GEFS  in S milder 20th, cooler 23rd, milder 27th, cooler 31st, Scotland somewhat similar but less marked swings and generally cooler wrt norm.  Runs fail to agree after Mon 25th and there are both cold and mild outliers throughout after that, Pptn doesn't really let up at any time exc briefly around Sat 23rd. 


ECM hangs on to the LP of the 21st for a day or two longer than does GFS but also subsides to a mobile westerly pattern by end of run


War does not determine who is right, only who is left - Bertrand Russell

Chichester 12m asl
Ally Pally Snowman
17 January 2021 08:05:53

Models firming up for a coldish spell  between 22nd and 26th. North likely will get some more snow. Then after that eyes drawn to some significant warmth to our south.


 


Early Spanish plume perhaps. 


https://www.wetterzentrale.de/en/topkarten.php?map=1&model=ecm&var=2&run=0&time=240&lid=OP&h=0&mv=0&tr=24#mapref


 


Bishop's Stortford 85m ASL.
CField
17 January 2021 08:07:29

Prove just how hard it is to forcast the weather....last night temperature forcast in Kent was +1 but reality was +5  to +6.


 


 


Favourite snowstorm
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Dec 31st 1978
Hastings East Sussex
Foot of level snow severe drifting
Next day max temp -4 degrees Celsius
doctormog
17 January 2021 08:19:03

Originally Posted by: Ally Pally Snowman 


Models firming up for a coldish spell  between 22nd and 26th. North likely will get some more snow. Then after that eyes drawn to some significant warmth to our south.


 


Early Spanish plume perhaps. 


https://www.wetterzentrale.de/en/topkarten.php?map=1&model=ecm&var=2&run=0&time=240&lid=OP&h=0&mv=0&tr=24#mapref


 



These are the corresponding ECM temperatures for the northern half of the British Isles at that point, a plume may be needed/welcome for defrosting purposes:


https://weather.us/model-charts/euro/9bf9b6df2472b53b5595bbf4f65d059f/min-temperature-6h/20210127-0000z.html 


 


 


Ally Pally Snowman
17 January 2021 08:36:29

Originally Posted by: doctormog 


 


These are the corresponding ECM temperatures for the northern half of the British Isles at that point, a plume may be needed/welcome for defrosting purposes:


https://weather.us/model-charts/euro/9bf9b6df2472b53b5595bbf4f65d059f/min-temperature-6h/20210127-0000z.html 


 


 



Decent snow cover factored in there. For the south looks a warm up around the 26th and if we can tap into the anomalous warmth in Iberia could be significant. 


Bishop's Stortford 85m ASL.
doctormog
17 January 2021 08:47:29

Originally Posted by: Ally Pally Snowman 


 


Decent snow cover factored in there. For the south looks a warm up around the 26th and if we can tap into the anomalous warmth in Iberia could be significant. 



It is possible, but I notice that on the GEFS suite, the t2m value for London is the warmest of all 30+ members on the 26th, with a notable split on that date. There’s a lot of water to pass under the bridge (both literally and figuratively) before then.


The Beast from the East
17 January 2021 09:02:30

Remarkable how all those drool charts have disappeared. Flooding now the real danger like last year, but worse as ground already saturated


 


"We have some alternative facts for you"
Kelly-Ann Conway - special adviser to the President
Gandalf The White
17 January 2021 09:09:19

Originally Posted by: The Beast from the East 


Remarkable how all those drool charts have disappeared. Flooding now the real danger like last year, but worse as ground already saturated


 



Yes, it’s pretty bad here already with one lane quite badly flooded and when we went for a walk a couple of days ago there was a new waterfall with flood water pouring off the field into the lane just down from us.  The field opposite is flooded once again.


Looks like the worst of it is for the west and north; not good.


Location: South Cambridgeshire
130 metres ASL
52.0N 0.1E


Roger Parsons
17 January 2021 09:13:42

Originally Posted by: Gandalf The White 


Yes, it’s pretty bad here already with one lane quite badly flooded and when we went for a walk a couple of days ago there was a new waterfall with flood water pouring off the field into the lane just down from us.  The field opposite is flooded once again.


Looks like the worst of it is for the west and north; not good.



River level results from our local station tell the same story. Gandalf!


We plan to take a walk down to see the what's happening today.


https://flood-warning-information.service.gov.uk/station/6073


Roger


RogerP
West Lindsey district of Lincolnshire
Everything taken together, here in Lincolnshire are more good things than man could have had the conscience to ask.
William Cobbett, in his Rural Rides - c.1830
surbitonweather
17 January 2021 09:24:54

Originally Posted by: The Beast from the East 


Remarkable how all those drool charts have disappeared. Flooding now the real danger like last year, but worse as ground already saturated


 


Another thing that is the same as last year is the amount of rain we’ve had with cold temps ie 5c. Very unpleasant & looking at the next 10 days, more of the same down here in SW London.......


Surbiton, Surrey 21m ASL
moomin75
17 January 2021 09:31:28

Originally Posted by: Ally Pally Snowman 


Models firming up for a coldish spell  between 22nd and 26th. North likely will get some more snow. Then after that eyes drawn to some significant warmth to our south.


 


Early Spanish plume perhaps. 


https://www.wetterzentrale.de/en/topkarten.php?map=1&model=ecm&var=2&run=0&time=240&lid=OP&h=0&mv=0&tr=24#mapref


 


Yes indeed. As I suggested a few days ago, I would not rule out some really quite exceptional warmth for a couple of days in the south with the GFS now hinting at temperatures approaching 15 or even 16c for a day or maybe two.


If the sun can come out (or even if it doesn't) that will feel positively springlike. Maybe even feel like an early May day in any sunshine.


Witney, Oxfordshire
100m ASL
doctormog
17 January 2021 09:42:26
In contrast, for the same places at the same time point the “new GFS” i.e. GFSP, has max temperatures between 1°C and 4°C. I wonder which option, if either, the 06z GFS op (and GFSP) will go for.
David M Porter
17 January 2021 09:47:24

Originally Posted by: moomin75 


Yes indeed. As I suggested a few days ago, I would not rule out some really quite exceptional warmth for a couple of days in the south with the GFS now hinting at temperatures approaching 15 or even 16c for a day or maybe two.


If the sun can come out (or even if it doesn't) that will feel positively springlike. Maybe even feel like an early May day in any sunshine.



With the sun still pretty low in the sky, I doubt that it would feel like early May with any amount of sunshine. A mild or very mild day in March might be a bit nearer the mark, IMO. Temps during a mild or very mild spell in March can easily reach above 15/16C given the right conditions; March 2012 saw temperatures somewhat higher than this for a sustained spell over much of the UK.


To be honest, the end of the coming week is as far ahead as I am prepared to look ahead to at the moment. There has been so much volatility and variability in the models beyond a few days ahead for such a while now that it has been virtually impossible to have any confidence in in one solution for more than a week ahead. Also, and as was mentioned earlier, the recent SSW may not have been fully taken account of by the models yet.


Lenzie, Glasgow

"Let us not take ourselves too seriously. None of us has a monopoly on wisdom, and we must always be ready to listen and respect other points of view."- Queen Elizabeth II 1926-2022
Russwirral
17 January 2021 09:54:04
The northwest gets stuck under a meandering front this week and looks to be aiming at 100mm of rainfall... more over the hills.

This means we are looking at maybe the 4th month in 6 with over 130mm rainfall in a month...

Weve had 50mm already


moomin75
17 January 2021 09:55:20

Originally Posted by: David M Porter 


 


With the sun still pretty low in the sky, I doubt that it would feel like early May with any amount of sunshine. A mild or very mild day in March might be a bit nearer the mark, IMO. Temps during a mild or very mild spell in March can easily reach above 15/16C given the right conditions; March 2012 saw temperatures somewhat higher than this for a sustained spell over much of the UK.


To be honest, the end of the coming week is as far ahead as I am prepared to look ahead to at the moment. There has been so much volatility and variability in the models beyond a few days ahead for such a while now that it has been virtually impossible to have any confidence in in one solution for more than a week ahead. Also, and as was mentioned earlier, the recent SSW may not have been fully taken account of by the models yet.


Keep believing David. I'm not going to quite write winter off just yet, but I have to be honest, I am very very close to doing so. Not for you up north I must admit, but down here, its been the dampest of damp squibs (yet again).


Witney, Oxfordshire
100m ASL
David M Porter
17 January 2021 10:04:26

Originally Posted by: moomin75 


Keep believing David. I'm not going to quite write winter off just yet, but I have to be honest, I am very very close to doing so. Not for you up north I must admit, but down here, its been the dampest of damp squibs (yet again).



I wouldn't be thinking of writing off the rest of winter when there is still 6 weeks of it to go, Kieren.


Had we had the same patten this winter that we had this time last year, i.e total atlantic domination, then I might have been more inclined to agree. However, from all that I have seen over the past month or two, there has been a great deal more volatility in FI in the models than I can ever recall being the case at any time last winter. With the recent/ongoing SSW, I reckon the amount of uncertainty increases even more.


It's worth remembering that the Beast from the East in 2018 didn't arrive until the final 2-3 days of February, and that wasn't long after we had had a brief milder and wetter spell in the middle of that month.


Lenzie, Glasgow

"Let us not take ourselves too seriously. None of us has a monopoly on wisdom, and we must always be ready to listen and respect other points of view."- Queen Elizabeth II 1926-2022
doctormog
17 January 2021 10:10:27

In the midst of discussion on isolated mid-teens temperatures at day 10 on one op run of one model, here’s the rather chilly picture at day 6 on the GFS 06z op:

https://www.wetterzentrale.de/maps/GFSOPEU06_144_1.png 



Narnia
17 January 2021 10:10:48
I would love not to look at the models for about five days and see the change in what is being forecasted now to what it would be then. I guess I would not recognise them with all the current volatility. Only problem is I don’t think I could!!!
Robertski
17 January 2021 10:12:34

For some it has been a decent winter, from an imby perspective I have seen lying snow 4 times.

For many a washout. The second warming is likely to distrupt our weather by the end of January.

According to the Met the first warming has had little to no effect on us, but the second one will.

So I'm ignoring output beyond 4 or 5 days.

moomin75
17 January 2021 10:22:09

Originally Posted by: David M Porter 


 


I wouldn't be thinking of writing off the rest of winter when there is still 6 weeks of it to go, Kieren.


Had we had the same patten this winter that we had this time last year, i.e total atlantic domination, then I might have been more inclined to agree. However, from all that I have seen over the past month or two, there has been a great deal more volatility in FI in the models than I can ever recall being the case at any time last winter. With the recent/ongoing SSW, I reckon the amount of uncertainty increases even more.


It's worth remembering that the Beast from the East in 2018 didn't arrive until the final 2-3 days of February, and that wasn't long after we had had a brief milder and wetter spell in the middle of that month.


Yes, but being a little pedantic, a cold spell in March, as was the Beast from the East was not meteorological winter. It was a cold start to spring. If there's nothing of note in February, then that is winter over. Of course we can get cold spells in spring and we usually do. In fact I've seen more cold in March than in any of the winter months in the last few years, but that doesn't mean its winter. It's a cold spring. Pedantic I know, but that's my view.


Also, I agree the synoptics are different, but the end product is much the same as a zonal onslaught - just the rain is colder. We have had loads and loads of rain recently and its unrelenting and flooding has been as much a concern this "winter" as in any other. We have had significant flooding in the town in the last six weeks and it doesn't matter whether it's mild rain or cold rain, it still floods the same way!


Witney, Oxfordshire
100m ASL
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