DEW
  • DEW
  • Advanced Member
27 May 2022 07:03:48

BBC WFTWA last night contrasting the GFS and ECM models for the Jubilee weekend, the former cool and damp with LP in the N Sea and NE-lies, the latter fine and sunny with HP and air from the south, but this isn't matched by this morning's output, with GFS better and ECM worse.


WX summaries, which are based on GFS, show uncertainty in this model. Yesterday there was a steady advance of warm weather on a broad front. Today they show this broad front in week 1 (cool N of a line Brittany - Alps - N Ukraine, warm S of this) breaking up quite dramatically in week 2 with a hot plume to Finland and modest warming for the UK while Germany and esp the Alps are cold. If that looks familiar, it's what GFS was forecasting a few days back, and it continues to oscillate between the two scenarios. As for rain, well distributed across Europe incl UK in week 1, mostly moving to C & E Europe week 2 with N Italy drenched. The NW Highlands never manage to shake off their own patch of damp.


Jet - bits and pieces affecting UK, nothing sustained. What there is, is mostly from the NW at first, through the Channel from Tue 31st, back to N-lies from Sun 5th, finally W-ly to the N of Scotland from Fri 10th.


GFS Op - subject to the caveats above, HP 1030mb Ireland and LP 995mb Baltic Sat 28th with N-lies for E coast. The HP moves to Iceland and the LP to cover UK Wed 1st with cool E-lies. The LP grudgingly retreats for the Jubilee weekend as pressure rises from the SW but not really clear until Tue 7th when a broad ridge of HP develops and is fully in place Sat 11th 1030mb aligned SW-NE


GEFS - in the SE dipping to cool (5C below norm) for Mon 30th, recovering to seasonal norm Thu 2nd and staying there but with some optimism for warmth from op & control ca Wed 8th. Small amounts of rain at any time. Similar temp profile in N & W (though control in these areas is an insane warm outlier +10C propping up the mean all by itself!) but more rain esp far NW and more frequently.


ECM - matches GFS to Wed 1st but the LP sinks a bit to the S (rather than moving NE) and brings in some warmth before broadening into a trough from Spain to Sweden, NE-lies again but HP centred 1035 mb Hebrides is dominant enough to affect all Britain Sun 5th. The LP gets closer on Mon 6th with E-gales for the Channel.


Confusing and unstable situation for a critical weekend.


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

Chichester 12m asl
GezM
  • GezM
  • Advanced Member
27 May 2022 09:41:21

Still a good deal of uncertainty about the weather for next week let alone beyond that. However, none of the options look especially inspiring with very little likelihood of anything particularly warm. At best we might briefly tap into some continental heat and there are hints of high pressure later in GFS. But we've already seen through May that distant promises very often never materialise!


I suppose we can comfort ourselves in the knowledge that there is no sign of prolonged wash out weather and if the sun does shine this time of year, it can feel very pleasant. Just make sure you layer up for the evenings if you are planning to stay outside  


Living in St Albans, Herts (116m asl)
Working at Luton Airport, Beds (160m asl)
Quantum
27 May 2022 14:53:32


This bubble of cold air is intense enough that we can't actually rule out snow to lower levels.


To be sure, it won't be easy; a torrential downpour would be required. But <1000m freezing levels make it possible. You probably also need the shower to occur at night.


Twitter: @QuantumOverlord (general), @MedicaneWatch (medicane/TC stuff)
2023/2024 Snow days (approx 850hpa temp):
29/11 (-6), 30/11 (-6), 02/12 (-5), 03/12 (-5), 04/12 (-3), 16/01 (-3), 18/01 (-8), 08/02 (-5)

Total: 8 days with snow/sleet falling.

2022/2023 Snow days (approx 850hpa temp):

18/12 (-1), 06/03 (-6), 08/03 (-8), 09/03 (-6), 10/03 (-8), 11/03 (-5), 14/03 (-6)

Total: 7 days with snow/sleet falling.

2021/2022 Snow days (approx 850hpa temp):

26/11 (-5), 27/11 (-7), 28/11 (-6), 02/12 (-6), 06/01 (-5), 07/01 (-6), 06/02 (-5), 19/02 (-5), 24/02 (-7), 30/03 (-7), 31/03 (-8), 01/04 (-8)
Total: 12 days with snow/sleet falling.
Saint Snow
27 May 2022 15:26:16

Still not looking terrible in the slightly longer term IMO.


No real warmth, but I'm not that arsed about that at this stage. Just prefer dry, usable weather - and, for the west especially, that looks a decent prospect as we move into June


 


 



Martin
Home: St Helens (26m asl) Work: Manchester (75m asl)
A TWO addict since 14/12/01
"How can wealth persuade poverty to use its political freedom to keep wealth in power? Here lies the whole art of Conservative politics."
Aneurin Bevan
idj20
27 May 2022 16:59:38

Earlier on today I've composed my own weekly "Farmers Forecast" on Facebook where I mentioned about high pressure moving in to settle things down by the following weekend all based on trends - then the latest 12z GFS come up with a complete about-face. Just hope it is just a rouge run and doesn't end up as being the final outcome, shouldn't be treated as an actual forecast at this point anyway.


Folkestone Harbour. 
moomin75
27 May 2022 17:26:02

Originally Posted by: idj20 


Earlier on today I've composed my own weekly "Farmers Forecast" on Facebook where I mentioned about high pressure moving in to settle things down by the following weekend all based on trends - then the latest 12z GFS come up with a complete about-face. Just hope it is just a rouge run and doesn't end up as being the final outcome, shouldn't be treated as an actual forecast at this point anyway.


The 12Z UKMO backs up your high pressure prediction though. Hopefully that is closer to the mark.


Witney, Oxfordshire
100m ASL
Ally Pally Snowman
27 May 2022 17:27:55

Originally Posted by: idj20 


Earlier on today I've composed my own weekly "Farmers Forecast" on Facebook where I mentioned about high pressure moving in to settle things down by the following weekend all based on trends - then the latest 12z GFS come up with a complete about-face. Just hope it is just a rouge run and doesn't end up as being the final outcome, shouldn't be treated as an actual forecast at this point anyway.



Could easily be the case . All models really struggling beyond 144h. 


Bishop's Stortford 85m ASL.
Saint Snow
27 May 2022 22:29:45

Originally Posted by: idj20 


Earlier on today I've composed my own weekly "Farmers Forecast" on Facebook where I mentioned about high pressure moving in to settle things down by the following weekend all based on trends - then the latest 12z GFS come up with a complete about-face. Just hope it is just a rouge run and doesn't end up as being the final outcome, shouldn't be treated as an actual forecast at this point anyway.



 


You mean a bit of a red herring?



18z looks alright so far 



Martin
Home: St Helens (26m asl) Work: Manchester (75m asl)
A TWO addict since 14/12/01
"How can wealth persuade poverty to use its political freedom to keep wealth in power? Here lies the whole art of Conservative politics."
Aneurin Bevan
Caz
  • Caz
  • Advanced Member
28 May 2022 06:45:06

Originally Posted by: Saint Snow 


 


 


You mean a bit of a red herring?



18z looks alright so far 


 


Market Warsop, North Nottinghamshire.
Join the fun and banter of the monthly CET competition.
Ally Pally Snowman
28 May 2022 07:00:41

This morning's output continues to be all over the place . For next weekend and beyond. 


Bishop's Stortford 85m ASL.
DEW
  • DEW
  • Advanced Member
28 May 2022 07:44:49

At the moment, I think I need two opposing summaries and post each on alternate days. There is certainly no consistency or as the BBC said "the models are struggling".


Today's WX is back to the broad advance of warmth on a broad front; the meridional pattern of yesterday which gave Germany some really cold weather has gone. Picking the 14C isotherm as a marker, the advancing warmth is from S England - Baltic - N Urals; or 18C, S France - S Germany - S Urals. Rainfall widely distributed across Europe in week 1 exc the Med which is dry; similar in week 2 except that Britain has got a well-defined 'blob' of its own.


GFS Op - current HP off Ireland disappearing into far northern latitudes and by Tue 31st shallow LP centred over Scotland and covering Britain. This fills slowly and Sat 4th weak ridge of HP from the west which is destroyed by LP from the north (with a bit of assistance from LP over France) before the end of the Jubilee weekend and looks very nasty by Tue 7th, centre 990mb Scotland and all Britain under 552 dam. This hangs around but finally clears N-wards by Mon 13th, replaced by HP 1025mb England


GEFS from cool in the next few days to mean temp near norm from Thu 2nd/Fri 3rd though poor agreement between ens members from this date (control has flipped from a dramatic hot outlier to one almost equally extreme cold). Significant rain week beginning Fri 3rd for the SE, more continuous rain elsewhere and heaviest for Scotland.


ECM like GFS until Sat 4th and then quite different: the weak ridge of HP develops strongly and is centred 1025 mb N Sea Mon 6th, with small LP just off Cornwall (could we get a sound and light show in the S for Mon evening to finish the weekend?). This LP moves to W of Ireland by Tue 5th with light S/SW-lies for UK.


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

Chichester 12m asl
moomin75
28 May 2022 10:21:03
6z GFS improving.
UKMO not bad either.
Witney, Oxfordshire
100m ASL
DEW
  • DEW
  • Advanced Member
28 May 2022 10:27:27

Originally Posted by: moomin75 

6z GFS improving.
UKMO not bad either.


Improved out of all recognition since 0z, I'd say. Even at only a week away, it's a bold forecaster who'd put money on a definite outcome for the Jubilee weekend


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

Chichester 12m asl
idj20
28 May 2022 12:51:10

Originally Posted by: moomin75 

6z GFS improving.
UKMO not bad either.



Yes, some cause for optimism this time round. Just hope this isn't another red herring.  


Folkestone Harbour. 
DEW
  • DEW
  • Advanced Member
28 May 2022 15:44:17

6z GFS was two steps forward; 12z is one step back.


You might just as well toss a coin as believe GFS at the moment.


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

Chichester 12m asl
DEW
  • DEW
  • Advanced Member
29 May 2022 07:03:50

BBC last night admitting that for the Jubilee weekend they still can't choose between GFS (HP to NW, dry and sunny but cool with winds from the N/NE) or ECM (LP to SW, warm but plenty of showers affecting England and Wales), as those models were last night.


But as it looks this morning:


WX temps - Europe warming up generally. By week 2 Europe S of the Alps hot, N of the Alps seasonally pleasant, except Scotland and Scandinavia still cool. Rain for most of continental Europe week 1, week 2 across the N (Iceland - N Scotland - Finland) with a patch in the Balkans. NW Scotland having a miserably wet summer.


Jet - not much at first but strong variously  from the W across Britain from Tue 7th


GFS Op - LP over Scandinavia drifts W-wards, filling,  to cover UK with slack LP by Wed 1st, then a modest pressure rise 1025mb Sun 5th giving way to Atlantic LP which moves to Hebrides 985mb Thu 9th. HP tries to move in from the SW Mon 13th but retreats again in the face of LP to the NE. [Jubilee weekend - modestly optimistic with HP further to the SE, some showers for the S on Fri, brisk SW-lies for the NW on Mon]


GEFS - cool now and again, less marked, around Tue 7th (esp op & control for the latter period) otherwise mean near norm. Different ens members offer small amounts of rain at any time anywhere but more in the NW


ECM - finally agreeing with GFS [Jubilee weekend, pressure a bit lower over France so maybe more showers at first, then HP more to the NE but still good for most of UK]


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

Chichester 12m asl
Ally Pally Snowman
29 May 2022 07:05:25

Models as clear as mud again this morning.  Although high pressure perhaps getting the upper hand in a week or so. But unconvincing atm.


 


Bishop's Stortford 85m ASL.
Taylor1740
29 May 2022 10:26:48
GFS 6z now not looking good at all for the BH weekend. Would be nasty on Friday if that came off. The thing that gets me is that the forecasters have seemed extremely confident in talking up the weather prospects for next weekend.
NW Leeds - 150m amsl
Hippydave
29 May 2022 10:28:24

Originally Posted by: Ally Pally Snowman 


Models as clear as mud again this morning.  Although high pressure perhaps getting the upper hand in a week or so. But unconvincing atm.


 



ECM IMBY is decent enough - relatively cool uppers at times but in strong sunshine it'll feel pleasant. There's not a lot of rain in todays 0z run, op very dry, ens in agreement until 2nd June when more scatter appears.


One possible 'blip' seems to be around T120 and how influential HP is versus a warm unstable push from the South/South West - think yesterday's ECM made more of that, today it scrapes the extreme south and I guess may bring some showers. After that LP tries to influence from the West and I imagine would throw rain there but little of it reaches here before the LP fills. 


In some ways it's interesting that we haven't had any bursts of serious heat yet. We've been a fair bit above average for most of the year CET wise and yet daytime highs haven't really deviated as much as you might have thought by the warm CET returns. I can't see that pattern holding for the whole summer, so a case of when we tap in some serious heat, not if IMO.


Home: Tunbridge Wells
Work: Tonbridge
tierradelfuego
29 May 2022 17:58:57

Originally Posted by: Hippydave 


 In some ways it's interesting that we haven't had any bursts of serious heat yet. We've been a fair bit above average for most of the year CET wise



 


Totally agree. Not that I have decades of data at our new house, but it seems like an odd year. There are some that would call the least 8 weeks or so cold, but they have been anything but, down in the south, it's just that there hasn't been a reasonably usual 26c+ day yet. The average daily max for May is way above average at 18c+. Having many days of 25c max and 15c min in May is not normal for the UK, and even with GW, will not be in our lifetime so a little perspective may be required in some quarters.


 


GFS12z looks usable, pretty much a follow on of what we have had recently, above average CET, pressure slack 1015 to 1025mb and temps moderated but above CET. Rainfall lower than average.


Bucklebury
West Berkshire Downs AONB
135m ASL
Users browsing this topic

    Ads