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Stormchaser
09 November 2014 23:41:52

Further to my comments regarding GFS missing convective elements, the 12z WRF-NMM run gives totals of 30-40 mm widely across southernmost counties:



This is most likely down to embedded convection being sustained for longer - getting further inland - after getting a boost from coastal convergence due to the southerly winds.


 


Regarding the longer range model output, it's a little strange how GFS and ECM models have toned down the Atlantic, with the jet tracking a lot further south, yet haven't produced much in the way of a strong ridge extending south from Greenland.


Guess we'll soon find out of that's a model shortfall or not.


 


The GFSP keeps on developing stronger troughs across the Northern Hemisphere than the other models, which breaks down the Arctic blocking in the 8-12 day time frame. I would say some things never change, but the current GFS has been happy to back off the idea so... I don't know.


It will be a concern for the GFSP model if we end up following the road with a quieter Atlantic that leaves the blocking to do its thing. If we don't... I'll be starting to develop some respect for it - though it appears unable to escape some serious flailing about past about 6 days range, with less in the way of run-to-run consistency than GFS and ECM over the past couple of days.


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chiversa
10 November 2014 00:42:05

hi everyone,
As we know ex hurricanes reaching our latitude can dramatically change the pattern of weather as Ex hurrican Bertha did Cristobal, did in October.
i was wondering if the effect, of Typhoon Nuri impact on the jet stream in the Pacific NW which has caused an unexpected plunge of cold air into the US will eventually 'ripple' across to us ?

http://edition.cnn.com/2014/11/09/us/cold-snap/
http://www.wunderground.com/blog/weatherhistorian/comment.html?entrynum=314

Alan

Hampshire

Originally Posted by: chiversa 


I wasn't saying the impact would mean we would get the same cold plunge, in fact last year extreme cold in the Mid west lead to the opposite effect here , and also note the Western US is going to be much warmer than usual. so we could  well  up the wrong side of any plunge and so toastier than expected!


https://twitter.com/EricHolthaus/status/530580970122915841/photo/1


Either way its interesting to watch..! glad it generated some comments!


 


Alan

nsrobins
10 November 2014 07:20:54

I'm reluctant to comment this morning as I don't seem to be able to hold the charts up the right way and see flat and inconclusive mean trends where others see warming ones.

Regardless of the minor details, the general theme continues this morning of rising heights to the N and NE into the second half of November. I am not in any shape or form forecasting an early wintry blast, but the chances of one occurring increase significantly with macro-synoptics such as we are seeing being modelled.


Neil
Fareham, Hampshire 28m ASL (near estuary)
Stormchaser, Member TORRO
nsrobins
10 November 2014 07:29:30

Very toasty for anything wandering around at about 50km above Europe later on:


http://www.instantweathermaps.com/GFS-php/showmap-strat.php?run=2014111000&var=TMP&lev=1mb&hour=384


Up at 1mb it will feel very mild indeed LOL.


Neil
Fareham, Hampshire 28m ASL (near estuary)
Stormchaser, Member TORRO
Matty H
10 November 2014 07:50:10

GFS ens remarkably flat, and remarkably good grouping, even in the latter stages. A sustained period of unsettled weather on the way (already underway). Brollys at the ready. 


Gooner
10 November 2014 07:56:06

http://modeles.meteociel.fr/modeles/navgem/runs/2014111000/navgemnh-0-180.png?10-06


 


Q's favourite looks good


Remember anything after T120 is really Just For Fun



Marcus
Banbury
North Oxfordshire
378 feet A S L


nickl
10 November 2014 08:08:55
Somewhere is gonna be very cold for November. (Apart from the states which we already knew about). I don't think it's going to be here - yet.

Maybe just cold here.

Essan
10 November 2014 08:10:05


Further to my comments regarding GFS missing convective elements, the 12z WRF-NMM run gives totals of 30-40 mm widely across southernmost counties:



Originally Posted by: Stormchaser 



I like the way the Vale of Evesham stands out on there (the roughly triangular patch of blue in the south Midlands) - clearly the models have cottoned on to the "Vale effect"


Andy
Evesham, Worcs, Albion - 35m asl
Weather & Earth Science News 

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Charmhills
10 November 2014 08:34:52


GFS ens remarkably flat, and remarkably good grouping, even in the latter stages. A sustained period of unsettled weather on the way (already underway). Brollys at the ready. 


Originally Posted by: Matty H 


I can't see anything to get excited about as of yet in terms of cold/or anything wintry.


Just unsettled and fairly wet at times.


Loughborough, EM.

Knowledge is power, ignorance is weakness.

Duane.
sizzle
10 November 2014 08:39:44

looks like london and easten parts will escape the unsettled wet windy weather this week. as looking mostly dry

GIBBY
10 November 2014 08:40:34

HERE IS MY LATEST ANALYSIS FROM THE OUTPUTS OF THE WEATHER COMPUTER PREDICTION MODELS FOR TWO WEEKS FROM 8AM TODAY MONDAY NOVEMBER 10TH 2014.


NEXT UPDATE TUESDAY NOVEMBER 11TH 08:00


THE CURRENT GENERAL SITUATION. A strengthening Southerly flow will carry a pair of fronts East into Western and Central areas later today, tonight and tomorrow.


MODELS-2 WEEK HEADLINE  Unsettled with rain at times across the British Isles with strong winds too and temperatures near to normal. perhaps becoming a little colder and drier from the North later.


THE JET STREAM ENSEMBLE FORECAST The GFS Jet Stream Ensemble forecast shows the flow maintained in a complex form but with the main core held to a position to the South of the UK for much of the period with varying strengths from day to day.


GFS OPERATIONAL Today's GFS operational run shows the UK under bombardment from Low pressure areas crossing the Atlantic and becoming slow moving close to the West and SW of the UK with repeated spells of rain and showers affecting the UK especially the South and West with mild Southerly winds for all. Through week 2 Low pressure edges further North for a time which only serves to bring more SW winds and quicker moving troughs running East and NE over the UK with sunshine and showers in between with temperatures close to average.


THE GFS PARALLEL RUN The GFS Parallel run carries the same sequence of events throughout with the northern High pressure to the NE collapsing later with a more direct hit of Atlantic wind, rain and gales for all as a result with Low pressure allowed to cross the UK directly rather than being held up just to our West.


THE GFS ENSEMBLES.  The GFS Ensembles are rather different through Week 2 as they allow High pressure to remain and in fact build to the North later in the output with the Low pressure areas afflicting Southern Britain in particular through Week 1 weakening and allowing a colder and drier Easterly flow to develop across the UK by the end of the period.


UKMO. UKMO today shows deep Low pressure over the Atlantic steadily slipping SE towards SW England at the end of the week with rain and heavy showers continuing as a result especially across South and West Britain while the North and NE could become rather drier next weekend with much cloud and sea mist rolling into Eastern and Central parts  in the East and SE flow.


THE FAX CHARTS  The Fax Charts show a series of slow moving occluded fronts with disturbances running North along them delivering copious rainfall across Western and Central Britain over the coming 48 hrs or so before a more gentle SW and showery flow crosses the UK for a time before renewed complex troughing attached to another deep Low West of Ireland moves into the UK from the SW by next weekend.


GEM  GEM shows Low pressure in total control of the UK weather over the next week to 10 days repeatedly moving into the UK from the west while filling slowly. Rain and showers look maintained across all areas over the period with little change in temperatures values to currently and strong winds at times.


NAVGEM NAVGEM keeps Low pressure domination across the UK and as other models show having reached UK shores they stall and fill slowly with rain and showers scattered about on most days. Some chillier air is shown to infiltrate Northern regions late in the run with Low pressure then in a belt across the Atlantic the South of the UK and into Europe with the cold air in the North edging further South with time.
ECM  ECM this morning shows little respite from the current pattern of Low pressure to the west and SW of the UK with stalling fronts running into Southern and Western Britain in particular with heavy rain at times here. Northern and Eastern parts could become somewhat drier as pressure is high to the NE. Little change looks likey to this overall pattern this side of Day 10 with temperatures holding near or somewhat above normal in mostly Southerly or SE winds.


THE ECM ENSEMBLES   The ensembles point to a continuation of broadly unsettled weather with rain at times across the UK in average temperatures and a SE flow as Low pressure continues to stretch from Southern Greenland to the SW of the UK. Some of the rain will be heavy and winds look like continuing quite strong at times. Pressure remains High to the NE of the UK at that time.


NOTABLE TREND CHANGES FROM PREVIOUS RUNS The trend today shows a somewhat reduced chance of High pressure developing to the North and NE bringing drier conditions to the North and East in Week 2 with slightly colder weather.


MY THOUGHTS  The pattern of a Jet flow blowing further South than it's normal position continues to offer the complex mix of Low pressure just to the West of the UK feeding decelerating troughs into the UK from the West and this looks like continuing for a long while yet. This means that rain will be heavy and prolonged at times as the troughs move in, slow or stall and this looks most likely over Western, Central and SW Britain for the next week or so. Beyond that things do complicate somewhat as there is still a variety of output still having a desire to enhance High pressure to develop from the North and NE later to at least bring drier and somewhat chillier conditions to the North and NE whereas it looks unlikely that this makes it''s way down to Southern Britain as the feed of Low pressure from the Western Atlantic continues to approach the SW at times with further rain as a result. In fact the GFS operational and Parallel runs show Northern blocking colllapsing entirely later with major Atlantic storms close to the NW oof Britain as a result. The amount of output showing any cooler solution has reduced somewhat and where it is shown it is in quite a diluted form with probably NAVGEM flying the chilliest resolution for the North a week from now. The GFS Ensembles don't look bad either for cold lovers down the line with a Scandinavian High developing but cold air is held at arm's length and just outside of the run term. However, with not much support from the ECM operational and it's Ensembles who maintain a cyclonic feed from a Southerly point across the UK it looks unlikely that we will see much more than a split in the Weather in a week to 10 days with the South and West continuing to see the risk of quite large amounts of frontal rain at times from slow moving troughs while the North and East gradually see drier conditions develop with time closer to High pressure to the NE with temperatures remaining close to average overall.


Martin G
Kilmersdon Radstock Bath Somerset



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Ally Pally Snowman
10 November 2014 09:23:49

I think the chances of UK cold with in two weeks is diminishing some what. The 10day Mean not so good today. Still has potential though.


http://www.wetterzentrale.de/pics/Reem2401.html


 


No support for cold in the Dutch ensembles either. Apart from the Control which goes very cold at the end. 


http://www.knmi.nl/exp/pluim/vijftiendaagse/index.php


 


I think any cold wont get to UK until December now.


Bishop's Stortford 85m ASL.
Gooner
10 November 2014 09:26:23


 


I can't see anything to get excited about as of yet in terms of cold/or anything wintry.


Just unsettled and fairly wet at times.


Originally Posted by: Charmhills 


As it is November 10th .................I agree.


Very early days and still in Autumn , plenty of time to start looking for the white stuff


Remember anything after T120 is really Just For Fun



Marcus
Banbury
North Oxfordshire
378 feet A S L


Frostbite80
10 November 2014 09:28:59


I think the chances of UK cold with in two weeks is diminishing some what. The 10day Mean not so good today. Still has potential though.


http://www.wetterzentrale.de/pics/Reem2401.html


 


No support for cold in the Dutch ensembles either. Apart from the Control which goes very cold at the end. 


http://www.knmi.nl/exp/pluim/vijftiendaagse/index.php


 


I think any cold wont get to UK until December now.


Originally Posted by: Ally Pally Snowman 

To be fair I don't think anyone was expecting anything cold this month but were/are looking at the patterns, which are totally different to last year. I do not personally believe we will experience anything really cold until the end of December onwards but that's just a hunch and would love to be proved wrong.

Gooner
10 November 2014 09:37:47


To be fair I don't think anyone was expecting anything cold this month but were/are looking at the patterns, which are totally different to last year. I do not personally believe we will experience anything really cold until the end of December onwards but that's just a hunch and would love to be proved wrong.


Originally Posted by: Frostbite80 


Fair shout and have to agree.


November is far too early for snow IMO


Remember anything after T120 is really Just For Fun



Marcus
Banbury
North Oxfordshire
378 feet A S L


Saint Snow
10 November 2014 09:49:56


To be fair I don't think anyone was expecting anything cold this month but were/are looking at the patterns, which are totally different to last year.


Originally Posted by: Frostbite80 


 


That was my take, too. I know in 2010 the cold set in late Nov, but I don't expect to see such a winter spell start so early for years, if at all.


As I've said many times, I'd rather any cold spell waited until mid-December. A freezing & snowy lead-up to Xmas would be ideal.



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
Frostbite80
10 November 2014 09:58:57


 


 


That was my take, too. I know in 2010 the cold set in late Nov, but I don't expect to see such a winter spell start so early for years, if at all.


As I've said many times, I'd rather any cold spell waited until mid-December. A freezing & snowy lead-up to Xmas would be ideal.


Originally Posted by: Saint Snow 

Agreed and to be fair with all the positives this year ie the record breaking SAI, easterly QBO, weak central based el Nino, Strat wave 1 and possibly wave 2 warming already a possibility as well as a very disorganised Polar Vortex and a potentially deeply negative OPI (soon to be known) I would be astonished if we don't go in the freezer at least once this winter.............if we don't I give up

Osprey
10 November 2014 10:01:11


 


Fair shout and have to agree.


November is far too early for snow IMO


Originally Posted by: Gooner 


 


November is hit and miss


What I don't want is a cold snap before Xmas week, after that, bring on some snow and frosts


Nobody likes a smartass, especially another smartass...
If it ain't broke, don't fix it!
nsrobins
10 November 2014 10:54:25


 


 


November is hit and miss


What I don't want is a cold snap before Xmas week, after that, bring on some snow and frosts


Originally Posted by: Osprey 


It's actually a great time to have a 'snap' - frosty, crisp days in mid-December make for a great atmosphere IMO.
Anyway, on topic and I am encouraged by the level heads today. I don't see any significant risk (30% +) of a decent cold shot before the end of November, but what I do see is a pattern that could easily lead to one. Last year and many times pre-2009 we would of welcomed the current synoptics if only for their potential.


Neil
Fareham, Hampshire 28m ASL (near estuary)
Stormchaser, Member TORRO
Gooner
10 November 2014 10:54:31


 


 


November is hit and miss


What I don't want is a cold snap before Xmas week, after that, bring on some snow and frosts


Originally Posted by: Osprey 


I must be alone in wanting a deep freeze from Dec 20th through to Jan 5th then, 60cm of snow -20 at night -8 during the day


Remember anything after T120 is really Just For Fun



Marcus
Banbury
North Oxfordshire
378 feet A S L


Ally Pally Snowman
10 November 2014 10:58:16


To be fair I don't think anyone was expecting anything cold this month but were/are looking at the patterns, which are totally different to last year. I do not personally believe we will experience anything really cold until the end of December onwards but that's just a hunch and would love to be proved wrong.


Originally Posted by: Frostbite80 


 


I think early December is a good shout. But as you say with so many positives we will be very unlucky to not get a cold spell this winter.


 


Bishop's Stortford 85m ASL.
Frostbite80
10 November 2014 11:06:54


 


I must be alone in wanting a deep freeze from Dec 20th through to Jan 5th then, 60cm of snow -20 at night -8 during the day


Originally Posted by: Gooner 

No Chance you can give me a bit of that to!!

Saint Snow
10 November 2014 11:25:16


 


I must be alone in wanting a deep freeze from Dec 20th through to Jan 5th then, 60cm of snow -20 at night -8 during the day


Originally Posted by: Gooner 


 


I'd take that in a heartbeat! Rather it started a week earlier though, and only ended a couple of weeks later



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
Solar Cycles
10 November 2014 11:25:51


 


I must be alone in wanting a deep freeze from Dec 20th through to Jan 5th then, 60cm of snow -20 at night -8 during the day


Originally Posted by: Gooner 

You are as January 5th is far too early, try April 1st.

Stormchaser
10 November 2014 12:15:59

This is becoming a bit of a hybrid model output/winter hopes thread - a bit of enthusiastic posting is fair enough but it's getting a bit much when half of the page doesn't discuss the models 


 


Speaking of the models, there's not a lot of change to report this morning, with the slow-moving frontal assault remaining in place for the coming week or so, and ECM still offering the most promising charts longer-term, while GFSP continues to obliterate much the Arctic blocking days 11-16.


From what I've read on other sites (lurking in its finest form), stratospheric warming continues to be modeled for the upper levels, and at quite a fast pace. If this propagates down as required to impact the troposphere and split or shatter the vortex, theory (namely Cohen's) predicts that we should actually see a period of neutral to positive AO conditions for a short time, followed by a dramatic reversal. The pace of developments currently being modeled suggests that this reversal could occur mid-December.


With this in mind, recent GFSP runs might actually have the right idea, though the +ve AO development does seem a bit too rapid.


 


It seems to me that a substantial cold outbreak across the UK this month would represent an unusual variation on the typical progression. November 2010 achieved that with a rare base-upward warming of the stratosphere that happened to be perfectly positioned to drive deep cold to the UK - resulting in a rapid and unusually early switch to a cold, snowy regime. This time around, a more common top-down warming is being signaled, hence the waiting game.


If you have any problems or queries relating to TWO you can Email [email protected]

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2023's Homeland Extremes:
T-Max: 30.2°C 9th Sep (...!) | T-Min: -7.1°C 22nd & 23rd Jan | Wettest Day: 25.9mm 2nd Nov | Ice Days: 1 (2nd Dec -1.3°C in freezing fog)
Keep Calm and Forecast On

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