DEW
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06 September 2021 06:02:40

No change from yesterday WX summary: this week's warmth (and a little rain - at the end of the week?) replaced by cooler air which sweeps in from the NW to cover central Europe, UK is on the edge of this and is dry for week 2 as bands of rain move S across the continent BBC more bullish about widespread rain on Thu/Fri than Meto or GEFS


GFS op - current HP dissipating and replaced with shallow trough over Thu./Fri to cover all UK not just Scotland as previously. HP soon re-asserts itself, first over Scotland Mon 13th, then a NW-SE ridge Jceland - Switxerland Fri 17th, while ex-hurricane Larry mibbls away at the SW. Larry breaks through as shallow LP moving close to S England into Europe Sat 18th with pressure rising behind to give new HP 1030mb N Sea Wed 22nd.


GEFS -current warmth is replaced by back-to-norm Thu 9th with some rain that day,more in the N than the S; thereafter mean stays close to norm and mainly dry (again. more rain in N than S) to end of run but with a lot of variation. Op & control suggesting a few cool and damp days most likely around Sat 18th 


ECM (early today so 12z) holds ex-Larry on the Atlantic extending a shallow trough across the UK so that the NW-SE ridge referred to lies further E (Norwegian Sea to Poland Tue 14th)


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

Chichester 12m asl
Bolty
06 September 2021 13:25:07
The last two runs of the GFS just show how hard it is to forecast in the medium ranges when there are ex-tropical systems in the mix. The UK remains under high pressure, yet the track for the mid-latitude remnant of Larry couldn't be any different. The previous run sends it beneath the UK high and close to France and then up to Ireland, whilst the 06Z has it travelling up the Eastern Seaboard and into Greenland. No doubt the 12Z will then do something completely different once again.

Of course I'm looking into too much detail, especially at this range, but it just shows how difficult September can be to forecast.
Scott
Blackrod, Lancashire (4 miles south of Chorley) at 156m asl.
My weather station 
Jiries
06 September 2021 17:31:07

Originally Posted by: Bolty 

The last two runs of the GFS just show how hard it is to forecast in the medium ranges when there are ex-tropical systems in the mix. The UK remains under high pressure, yet the track for the mid-latitude remnant of Larry couldn't be any different. The previous run sends it beneath the UK high and close to France and then up to Ireland, whilst the 06Z has it travelling up the Eastern Seaboard and into Greenland. No doubt the 12Z will then do something completely different once again.

Of course I'm looking into too much detail, especially at this range, but it just shows how difficult September can be to forecast.


Thing is at least with hurricane around made better HP cells and LP cells and move faster than slack ones we suffered this summer.  If huirricane start in May onward we would be having serious of very hot spells with brief unsettled spells.  We both watched the BBC forecast last night that show the cold cloudy HP being kicked out to Europe and told my wife about that and told her good riddance to this HP we better off with on edge of HP systems with S or SE flow than over us that stay overcast.

DEW
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06 September 2021 21:10:30

Originally Posted by: Bolty 

The last two runs of the GFS just show how hard it is to forecast in the medium ranges when there are ex-tropical systems in the mix. The UK remains under high pressure, yet the track for the mid-latitude remnant of Larry couldn't be any different. The previous run sends it beneath the UK high and close to France and then up to Ireland, whilst the 06Z has it travelling up the Eastern Seaboard and into Greenland. No doubt the 12Z will then do something completely different once again.

Of course I'm looking into too much detail, especially at this range, but it just shows how difficult September can be to forecast.


Meteo Group (BBC) and 12z agree on Larry heading to Greenland, GFS having changed its mind since the 0z


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

Chichester 12m asl
BJBlake
06 September 2021 22:38:28

Starting to see rapid cooling in the North Pole and early snows for the extreme east of Siberia: Should see the end of the summer ice melt soon.  Jet seems quite amplified still on recent runs - with less cold pooling over the pole: The polar vortex is weaker on more recent runs for much of September, which could point to greater blocking and periods of dry, settled and sometimes hot weather for our location..Its all about the centre of those blocking highs now.


Brecklands, South Norfolk 28m ASL
DEW
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07 September 2021 06:53:31

WX summaries show waem wether just about hanging on for the SE, but but week 2 Scotland and most of N Europe quite cool. Rain in SE week 1, in NW week 2.


jet ; mostly staying away for now; UK catches the edge of a loop centred near Iceland Mon 13th but a more S-ly line affecting first England then Scotland from Sun 19th


GFS op; trough briefly across UK Thu/Fri but HP back pver Scotland 1025mb Mon 13th drifting E-wards and allowing trough to affect Ireland Thu 16th; resolving into ridge N Spain to Baltic Mon 20th with Sw-lies for all evebntually becoming S-lies by Thu 23rd. Ex-hurricane Larry not much in evidence.


GEFS ; temps dip to a iittle below norm by Mon 13th but rise again Thu 16th before mean resumes norm for rest of run Plenty of variation after 13th. Small spike of rain  on Thu, then rather dry in S but more in N though many runs remain dry.


ECM ; similar to GFS though keen to develop LP over S France later from Wed 15th may affect S coast


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

Chichester 12m asl
DEW
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08 September 2021 08:22:26

A bit late this morning - car taken in for service & Mot


WX summary - cool and not a little damp for the next two weeks, along with much of N & C Europe


GFS - tomorrow's trough moving off NE-wards, followed by a rather unconvincing rise in pressure - a sort of SW-NE ridge but with LP close on either side. these LPs join forces Sun 19th and resolve into major Lp 975mb Hebrides Fri 24th. 


GEFS - temps descending to norm Mon 13th and mean then staying there throughout with increasing uncertainty. Op & control favour cool weather Mon 13th & Sun 19th. Occasional bursts of rain but not much of it and not in every run


ECM - like GFS but more emphasis on the European LP Wed 15th and the Atlantic one Sat 18th


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

Chichester 12m asl
Taylor1740
08 September 2021 09:27:07
Looks like the cool, cloudy high may be returning for the weekend and next week.
NW Leeds - 150m amsl
DEW
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09 September 2021 07:22:37

WX summaries: week 1, still a bit of warmth holding on in the SE, rain around generally; week 2,any warmth just fringing Cornwall and down into W France, most of N Europe looking cold, rain for UK mainly in Wales & NW


Jet : rather fragmented at first and not affecting UK until Thu 16th when it begins to run across England eventually looping around UK Mon 20th before retreating to Atlantic Sat 25th and forming a cut-off low W of Ireland 


GFS: current trough moves away NE -wards leaving a region of slack (mainly low)pressure until Fri 17th when LP 975mb Rockall and then crosses UK by Mon 20th. LP then sets up on Atlantic drifting S-wards from Iceland to Biscay over that week with UK under warm S-lies (not matching WX!) and finishing with strong ridge from Baltic Fri 24th


GEFS: different from yesterday (Chris Fawkes on BBC last night was also emphasising uncertainty) - temp at seasonal norm this weekend, warm Tue 14th, cool Sun 19th, hint of warming thereafter, rain in S from Tue 14th and most likely around Tue 21st; in N some rain on and off throughout. Current forecast of storms over the next 2 days not  reflected in GEFS for the S


ECM: similar to GFS but the 'slack pressure' is a rather higher and the LP on Fri 17th stays out west before beginning the sequence of LP on the Atlantic


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

Chichester 12m asl
The Beast from the East
09 September 2021 08:02:35

Still some warm uppers for so late in the season


Modele UKMO - Carte prévisions


"We have some alternative facts for you"
Kelly-Ann Conway - special adviser to the President
Bertwhistle
09 September 2021 19:19:49

Don't think anyone knows what's going on at the moment and Nick Miller was quite honest about this in the Beeb's weekly outlook tonight.


Control has flipped from high outlier to low outlier at the end of the current GFS output.


Lack of posting could also reflect the uncertainty.


I have a feeling the Atlantic won't have the hand it usually does through September despite the hurricane activity. 


Bertie, Itchen Valley.
'We'll never see 40 celsius in this country'.
DEW
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10 September 2021 07:16:56

Wx summary slightly more optimistic for moderate warmth hanging on in the S for a couple of weeks, nbut definitely cooler in far N; rain pattern has shifted since yesterday with some here and there irregularly week 1 but a dousing for all week 2


Jet not affecting UK directly until Sat 17th and then a complex pattern of loops and streaks means that a strong flow visits all parts of the UK in turn for the following week.


GFS: curent trough moves away tot the E, then some rise of pressure though UK still affected by shallow trough from SW wed 15th. After Fri 17th the Atlantic is the major influence with centres between Scotland and Iceland generating a mostly SW-ly flow until Thu 23rd when it moves SE and is 980mb Hebrides Fri 24th before resuming station on Sun 26th


GEFS: temps a little above seasonal norm ca Thu 15th, a little below Mon 19th; plenty of variation up to that point and absolute mayhem thereafter. More rain than forecast yesterday, well distributed. If anything, Scotland cooler and drier in the immediate future.


ECM: similar to GFS though final frame shows an interesting strong rise of pressure from the SW Mon 20th


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

Chichester 12m asl
Russwirral
10 September 2021 15:07:05
Just the slightest hint that the HP to the east might prolong its stay and we open up a southerly blast next week...

this weekends runs will be interesting to see if we go straight to another breakdown - or if we get a warm late summer plume
DEW
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11 September 2021 07:25:15

The models are having a problem over the next couple of days with a small but active LP in the west. BBC last night thought it might affect Cornwall but FAX this morning shows it running up the coast of Wales to W Scotland; at the same time a small Channel low is pushing showery troughs  N-wards so the Midlands might get some significant rain too especially if the systems combine.


The summaries show avearge to warm temps in S, cooler in N; rain randomly occurring week 1, more in the W week 2, indeed the E coast (unlike yesterday) almost dry


Jet less active around the UK than shown yesterday, almost nothing affecting UK until Fri 17th when the leading edge of loops on the Atlantic give a S-ly flow just off the W coast  on and off to FRi 24th when bits break off to go across the UK


GFS op: pressure fairly high across UK but with occasional shallow embedded troughs (sounds familiar?) until Thu 23rd when the LP on the Atlantic (which has been  threatening) gets closer and brings up warm S-lies before a piece of it breaks off and runs across Cornwall Sat 25th. The main LP then retreats W-wards and by Mon 27th the controlling feature is a large HP 1035mb Norway with E-lies for the S, calm elsewhere.


GEFS: temps mostly close to (in the N) or a little above (in the S) seasonal norm for next two weeks, fairly good agreement between runs to Sun 19th after which no guarantees; mostly dry - some splashes of rain in the next few  days, perhaps more at end of period in the E, more persistent but not heavy in the W.


ECM: similar to GFS to Thu 16th but then promotes LP on the Atlantic with first system then running N of Scotland with W-lies before a second LP establishes off SW Ireland with HP and warm SE-lies for UK. Quite a difference so keep watching!


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

Chichester 12m asl
Bertwhistle
11 September 2021 09:34:17

A really persistent set up continuing in some parts of Europe with low pressure refusing to relinquish ground over NW Russia leading to pink precipitation most days from mid-month in the GFS Op; even Moscow has snow-row options daily.


https://www.theweatheroutlook.com/twodata/gefs.aspx?run=na&lg=850&lglocation=moscow_russia&charthour=006&chartname=ps_500hpa&chartregion=na-region&p=1&charttag=PS%20500hPa%20(GPDM)


At the same time HP to our E means Atlantic lows fail repeatedly to win for any length of time and further warm spells lift temperatures to low-mid twenties at times.


Bertie, Itchen Valley.
'We'll never see 40 celsius in this country'.
ballamar
11 September 2021 11:25:14
Beast from the east followed by reload from north……sorry 😂
DEW
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12 September 2021 06:59:39

Summary maps: UK, W France and Spain hanging on to some warm weather for the next 2 weeks butrest of Europe looking rather cold. Mainly dry for UK except far NW, rain areas mostly over Pyrenees, Alps and later Balkans


Jet - bits and pieces close to W Coast for ths week , then a more concentrated flow (not shown yesterday) across Scotland Tue 21st before looping away to the N.


GFS - pressure fairly high across Uk for the next week or so on a SW-NE axis, with each side being nibbled at by LP (so SW-lies in N and NE-lies in S, and perhaps an occasional trough drifting in as for instance tomorrow). These two areas of LP join up briefly on Tue 21st before a strong rise of pressure from the SW (1030mb widely from Sat 25th)


GEFS - temps close to or slightly above seasonal norm with good agreement to Tue 21st, after that mre scatter but a hint of more warmth. A little rain in the next couple of days from that troublesome trough then rather dry in the SE occasional rain in W & NW


ECM - has the area of HP further S and more Atlantic influence for the N at first; then the Atlantic is more active generating LP close to NW Scotland Fri 17th  and others 1005mb Clyde Mon 20th, 995mb Orkney Wed 22nd. The large HP to the NE shown yesterday for Tue 21st is no longer to be seen


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

Chichester 12m asl
DEW
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13 September 2021 07:23:20

Summary maps: some warmth pushing in from the west as Europe cools down over the next couple of weeks. Rain distributed across the UK, more concentrated in far NW later


Jet looping on the Atlantic with the leading (S-ly ) edge of the loop nor far from Ireland until Thu 23rd when first the loop and then a direct W-ly jet across UK This breaks up after  3 or 4 days to leave a cut-off over Portugal and some W-ly streaks near Scotland Wed 29th


GFS looking more like yesterday's ECM. Current shallow trough taking its time to clear E-wards (to Thu) then a pressure rise from the SW settling over SE England Sun 19th before Atlantic trough pushes it aside Wed 22nd. Another HP cell from the SW to SE England Mon 27th not lasting as trough from Iberia to Norway appears by Wed 29th


GEFS temps briefly warm at first before a long period with mean close to seasonal norm and variations between runs increasing considerably after Wed 22nd. A little rain at first, then mainly dry but with increasing probability of rain from that date


ECM broadly similar to GFS  though pressure rise over the S is less clear


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

Chichester 12m asl
DEW
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14 September 2021 06:51:09

WX summaries showing warmth retreating to the SW, more so than yesterday, while N Europe is distinctly cooler. Fairly dry in the SE but rain encroaching from the NW over the wo weeks.


jet - main action os on the Atlantic as yesterday, but this morning's charts show more fragments breaking off to affect the UK from time to time, nothing systematic; Sun 19th W Scotland from S, Tue 21st Cornwall from NW, Sat 25th Scotland from SW, Wed 29th Ireland from W


GFS - a rather messy picture of fairly high pressure but with troughs breaking in from time to time (notably Sat 18th) for the next week but a more definite HP Wed 22nd 1025mb SW England with strong SW-ly winds just about hanging on to Sat 25th when Atlantic W-lies take over. Some sub-552 dam appearing over the N at end of run, and in general does not match the summary charts well.


GEFS - Fair agreement between runs on temps close to seasonal norm to Mon 20th after which mean stays near norm but with more variation than previously and both op & Control as outrageously cold outliers in the S (control 12c below on 22nd) but the same two runs well above norm in the N. Rain now and intermittently from 20th again with a few ridiculously high peaks. I wouldn't trust much of this after a week from now


ECM - agrees with GFS though slower to develop the HP in a week's time


EDIT - A hat-trick of posts without reply. Is everyone else feeling baffled?


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

Chichester 12m asl
chelsea4cup
14 September 2021 08:01:43

Thanks Dew for the update, We go on holiday on 26th September to the Lake district then onto Whitby, I really have no idea what weather we will get. Need to wait until after the weekend to see what really is coming. Long range outlooks still seem to say that high pressure will rule in October.


Phil, York
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