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This is the sort of pattern I envisage setting up and repeating all winter.

More urgently Steve.... Get your phone charged

12z GFS moving to the UKMO evolution that its been touting for the last 36-48 hours Snow showers to lower levels in Northern Scotland & possibly Shetland...

Not much to add to previous comments. With the center of the high pressure remaining in the west the resultant ridge influencing the UK will always be under pressure from the energy exiting N. America driving systems around it and thus, as always in this situation, a tendency for a N/S split. Having said that there is nothing particularly alarming in the woodshed in the short range with positive anomalies in the Atlantic apart that is from some rather cool temps. .Last evening's EPS anomaly illustrates it pretty well. This morning sees the high pressure in charge as the very weak cold front continues to drift south, eventually into France. Thus still some cloud around in some central southern and eastern regions but this should clear fairly quickly giving a sunny day with light winds in all areas with perhaps the odd shower in the north of Scotland.where it will also be a tad breezier. But noticeable cooler than of late. The clear skies and light winds will continue this evening and overnight leading to quite a chilly start to Saturday with some widespread ground frost. It will continue to be sunny in England and Wales through Saturday bur a cold front associated with the low tracking NE to be west of Norway is approaching the north west and will bring rain and strengthening winds into western Scotland and N. Ireland by evening. The cold front will continue to track south east and weaken as it goes through Sunday but it will briefly introduce a cooler, showery, regime in it's wake as the surface wind veers to the NW/N South of the front it will be mainly sunny. Once the front is out of the way the ridge again reasserts itself leading a pretty sunny day on Monday, albeit not overly warm, but another low is tracking into the Iceland area and the associated fronts will bring rain and strengthening winds to N. Ireland and Scotland by evening. This shunts the colder air east but only of course to start the whole process over again. Actually this is not quite true as this low is driven on a more easterly track as the high cell is nudged a tad further south and thus pretty windy over the north on Tuesday and showers generally as the frontal system is driven south east during the day. And the NH profile at T120

Expect a little bit of an uptick in the snow cover chart over eastern Siberia. The snowfalls have been mostly over high ground so far, but in the last couple of days low pressure to the north of the sea of Okhotsk is producing quite widespread snow inland (still more to higher ground at this stage - Delyankir 22cm at 802m asl). After a couple of dustings, Ojmjakon (745m asl) reported 9cm of snow at 21:00 yesterday (6am today their time), looks like this may now last the winter. Extremely mild air flooding into the eastern arctic in the next few days isn't expected to reach this far south and the average date of continuous snow reporting (1999-2013) was 3rd October, ranging from Sept 17th in 2012 to Oct 20th in 2003. As the nights are now longer than the days the net radiation loss quickly picks up leading to the formation of a deep inversion and surface high pressure. This lead to the rival cold pole capital the lower altitude Verhojansk (137m asl) not receiving a permanent snow cover til 2nd November 2008 compared to their average date of October 8th though temperatures had already fallen as low as -27.7°C before the end of October (with 1cm of snow).

I see the annual combination of the Daily Mail and Exacta Weather has started their nonsense winter predictions! I hope you all had a great summer

I posted this in the model tweets thread seven minutes before you posted it in here ha ha of which i thought was more appropiate but i guess it isn't a bad idea to post it in here so that a lot more people know about it,as if we haven't got enough models to look at esp the gfs and gfs parallele four times a day,i suppose the more data the better but i hope it goes out to t240 just like the 0z/12z as for the models,there is a lot of chopping and changing going on prob due to four storms/hurricaines around the globe at the moment throwing uncertainties into the mix in western and eastern Pacific the Alantic and in the Med(black cirlcles) plus also that huge +ve heights over Alaska and into the pole(red circle) gfs 12z t06hrs for example until things settle down it's going to be a topsy turvy ride on a final note:-

Frosty start, sunny daytime now overcast evening. Still. Chickens never seen frost before and they looked unimpressed.

There's going to be an ECM pub run?! Make it happen, @SylvainTV.

If we were further into the late autumn/early winter season the current synoptic set-up might be raising a few eyebrows in here! The World Climate Service reporting a record breaking persistent block impacting Alaska: "The Sep 1-20 detrended 500mb height anomaly just south of the Bering Strait was the most positive 20-day standardized anomaly on record (1958-present) anywhere in the globe (+5.2 standard deviations, R1 data)." https://twitter.com/WorldClimateSvc/status/1045015726183133185 And with the block still in place 7 days on and cross Polar ridging, plus a GEFS forecast of negative 10hPa AO Index out to Oct 11th, the fledgling Strat Polar Vortex is (for now) not being allowed an easy start to the season. It will be interesting to see how the current coupled troposphere/stratosphere develops from here. Based on the latest GEFS forecast http://weatheriscool.com/ is reporting: "The strat. vortex is currently weaker than ERA interim average and is forecasted to remain weaker than average (according to EPS-mean) 0 of 21 members have stronger vortex than average at the last forecast step (2018-10-12 00:00:00)." Here's an illustration from the paper Blocking precursors to stratospheric sudden warming events that shows how a persistent block in the eastern Pacific/Alaska area can often (but not always) be a precursor to a Vortex splitting event. Full paper: https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2009GL038776 But as @Interitus has shown above, all this not particularly indicative of how the SPV progresses from here. So best viewed as something to whet the appetite at this stage!!

I have a similar problem with gin been known to end up in wrong bed with neighbours wife

Beer going down lovely heating still on

Guess we will have to see .. ECM showing a colder northerly flow as we move towards the end of next week, i'd wager some ground frosts under clear skies, northern England northwards..

Long sunny periods today but only about 14C rather than 21C yesterday and the day feels cold. Suspect tonight will be even colder than recent nights, possibly even frosty? Currently clear and calm.

Central heating onnnnnn

I did some basic correlations between September sea ice extent and winter CET a few years ago. Here's the thread/comment: Could probably do with some updating!

More or less certain to finish on 13.9C before corrections are applied. 14.1 or 14.2C on tomorrows update, then 14.0C to the 29th, and 13.9C to the 30th

First notable frost of the season here too. Cars, grass and roofs all frozen. Disappeared quickly in the sun.

Another stunning morning here, going to feel decent enough today & tomorrow in the sunshine. Still enough strength in the sun to feel pleasant. No rain or bore fest low pressure in the next 7-10 days apart from a possible drop of rain Tuesday morning. Great weekend coming up for those of us that get out & about, making the most of it before the crap weather really sets in.

Morning All, well its the first cloudy morning for quite a while. still mild though. Weekend is looking nice for walking the dog :)

Just a focus on the nearer term output today. Some mostly settled weather in the next few days for places with further sunny spells in places continuing a similar theme earlier this week with High Pressure in control, especially so in the South. Towards the weekend, however, the models show Low Pressure to the North-West swinging South-Eastwards bringing wind and rain over Northern areas. But as the Low Pressure drops to the South-East, the models show the flow briefly turning to the North during Sunday with some showers likely for Northern and some Eastern areas. The flow looks as though it should be cold enough for the snow switch to get turned on over the Scottish mountains. But doesn’t look as though there’ll be too much of the white stuff. Mild to warm during the day times in the South, particularly in the sunnier periods, but generally a bit cooler in the North with temperatures more in the lower teens - perhaps into single digits in some places in the far North. But with the cooler flow from the North on Sunday and into Monday, then more places in the North could see temperatures more into the single digits. Daytime maximum temperatures: Nightime minimum temperatures: Sunday night and into Monday morning looks to be the coldest period in general with temperatures probably unlikely to get above freezing in some Northern spots. Especially during clearer skies. Could be quite frosty for some Northern parts that morning. Though nights in general look to be quite chilly in for all areas at times.

This weekend's Medicane is looking to have some severe impacts on Greece and Turkey. Here's some extracts from the update published late Thurs 27th Sept by Severe Weather EU: Rapid cyclogenesis is ongoing just off the Libyan coast this evening, central surface pressure is around 1004 mbar. The cyclone is expected to move due north and intensify over the Ionian sea tomorrow during the day before it turns east towards southern Greece and continues towards the Aegean sea and the western Turkey on Sunday. Saturday, 29th Sept 12 UTC – models mostly agree on the potential track of Medicane across the southern Greece, the centre / eye should eventually track between Peloponnese and Crete Island. The Medicane’s eyewall would in this case effect both landmasses pretty hard! Peak wind gusts could reach 120-150 km/h based on high resolution models. Sunday, 30th Sept 12 UTC – all models also push Medicane into the Aegean sea and then also into western Turkey. This would bring potentially devastating flash floods there as severe storms with torrential rainfall could produce huge amounts of rainfall across the steep slopes in mountainous terrain of the western Turkey. Models are also on track in hinting at a potentially extreme amount of rainfall. Southern Greece will get hit hard, regardless of the track. These are the latest model guidance updates from GFS, ARPEGE and ICON-EU models – 300-500 mm may well be possible in some areas and bring life-threatening flash floods. Source: Severe Weather EU: http://www.severe-weather.eu/mcd/update-medicane-forms-over-the-ionian-sea-tonight-expected-to-cross-greece-on-saturday-and-head-to-western-turkey-on-sunday/ IR satellite image Fri Sept 28th with the toe of Italy above (to the north) of the storm and Greece to the right: Animation of maximum wind gusts from GFS Greece Model for Fri 28th - Sun 30th: Charts courtesy of http://www.meteociel.fr/

We are set for some interesting times. http://spaceweather.com/ THE CHILL OF SOLAR MINIMUM: The sun is entering one of the deepest Solar Minima of the Space Age. Sunspots have been absent for most of 2018, and the sun's ultraviolet output has sharply dropped. New research shows that Earth's upper atmosphere is responding. "We see a cooling trend," says Martin Mlynczak of NASA's Langley Research Center. "High above Earth's surface near the edge of space, our atmosphere is losing heat energy. If current trends continue, the upper atmosphere could soon set a Space Age record for cold."

Cold late September 1919,air frost and snow.

Its a time serious of tropical anomolies. The reds are in effect westerlies and blue easterlies. Where they sit can influence our weather down the line. You can see a diagonal red which shows a wave passing through the Pacific adding westerlies to the atmosphere and enhancing mid latitude blocking.

I've got two, as my motorcycling days seem to be over. Heart failure means I don't have the stamina to pedal a standard bike. Both of mine are a bit naughty as both are "Power on Demand" with motorcycle-style twistgrip "throttles", with pedelecs the motor only runs as long as you are turning the pedals but a lot of e-bike riders have the same type as mine. Power is still limited to 250W and max. assisted speed 25km hr or 15.5mph, should you exceed that speed the motor shuts down. Decathlon do one for about £700, my Rich Bit cost £1300. The Rich Bit has 21 speed dérailleur gears so can be ridden as a conventional albeit heavy mountain bike. Alloy frame and magnesium wheels. The 36v LiIon battery is inside the frame, it's a folder so folding the frame gives access to the battery although charging is via a socket on the frame.

There's some analogue evidence for short, deep minimums however 2008/2009 for example was an alternative anonomy (not the only one). I personally suspect this one will be another long one and near record breaking.

Looks like extra runs from ECM are coming our way "Just heard word that ECMWF will soon be providing 6Z and 18Z cycles (in addition to the 0/12Z runs). This will be hourly data from 0 to 90 hours and 3-hourly data from 93 to 144 hours for 00/06/12/18Z runs. Good news to start the day!"

Evening All - Its been a long long time since I opened a thread - So I will try to make it interesting... The first dip of the toe into Autumn is for many of us the change in mindset away from summer heat & into the ever shortening days & colder weather... Traditionally as we head through September & especially October the vortex & westerly jet increases to a point where the probability of southerly warmth is significantly reduced in probability- Notable dates in the diary for this is around the 10th of October onwards where the winter time Stratospheric vortex is ~ half of its winter peak speed @ ~ 16-20 M/S Westerly. Shapes of high pressure through 40- 50N should be flat & the mode of the AO / NAO historically reads as a positive... There is one other important Teleconnection that I never hear anyone ever mention but Ive kept revisiting it each winter for about the last 5 / 6 years is the POL ( the polar eurasia pattern ) The loading pattern for POSTIVE PHASE is measured across Northern Russia down to about Mongolia & is a similar measure to the NAO - The more POSITIVE the phase the lower the geopotential heights are over Norther Russia supporting a westerly circulation So + AO + NAO + POL all indicate a traditional zonal flow. To emphasise this the 90s was where the jet was roaring & the AO & POL certainly in autumn months peaked heavily positive So all said & done taking into consideration natural variation between occasional stronger & weaker years & of course ENSO phases we generally see a uniform process to our weather through Autumn which decends into 'westerlyness' - & this years Autumn forecast would seemingly be very straight forward if you wanted to pluck out things like matches from ENSO state & QBO phase & of course they 'could' still play their part however ENSO will be solid Neutral for SON & QBO will be dwindling Easterly - Anyway- What changes do we see potentially impacting our weather & the imposed 'Westerlyness' ... Pattern Induced Climate change is probably a phrase thats not bantered about to much but it certainly will be in the coming years- The globe is warming however the poles are warming much faster than the average annual rate - this is creating a NEW ( circa 2007 onwards ) feedback loop over the polar cell & * SOME * of the mid lattitudes - It is causing autumn tropospheric decoupling from the stratospheric vortex & it occurs in the low sea ice areas ( or more specifically the areas with the biggest negative anomaly to the norm ) What we have seen since 2007 is not only the decadal average of sea ice decline ( especially August / Sept & Oct ) but also focal points of significant negative anomalies in areas close to where the POL teleconnection is measured. The Barents / kara & laptev seas have all been in the 'ice news' for the wrong reasons & the graphs below show how this summers ice coverage has taken a real beating - The 3 above are in Anticlockwise order from Scandi Eastwards - Notes being * Barents melting out early like the decadal Trend * The next in line Laptev taking a further hit this year - being probably the worst on record * Kara as well - under the decadal ave & close on record lows - - Its also worth noting how far away they are from the 70s / 80s are - imagine how far they would be from the 50s & 60s ! The net fallout from this is the amount of residual latent heat in these areas through Autumn & *Possibly* now Early Winter & what the net fall out is - the creation of a new feedback loop of Positive heights In Northern Russia. This is also probably the net reason 'globally' why there is a reduction in the overall jet speed & depth of negative geopotential heights because of the reduced Thermal Gradient.. This illustrates well if you chunk up Sept & Oct 500 height anomalies charts for 1948 -1990 The base period 1990 - 2006 a fairly significant 16 year phase of ice loss 2007 -2017 the last 10 years in ice loss creating this new feedback loop & pattern change. We see a CLEAR Modal change in the height field over the pole - especially concentrated over the 3 weak ice areas. Lets reintroduce the POL teleconnction to include the last decade The mode has swing to a very sharp -POL especially in Autumn but not exclusive. The data indicates ftp://ftp.cpc.ncep.noaa.gov/wd52dg/data/indices/poleur_index.tim That 2007-2017 Sep / Oct / Nov 20/30 months have been negative with 9/9 on the last 3 Autumns !!! 100% Its also about the 'negativity' of the mode as well - going off the scale more recently.. So Bringing that back to this Autumn & NW Europe the net effect is that the eastward propergation of the atlantic is expected to be weaker & weaker - so for Western Russia we could be promoting an earlier signal for Colder weather developing - This signal fades as we come SW towards Norther & Central Europe, however the extent of the high promotes higher probability of early warmth from the south but again later into Autumn could also promote Colder air filtering through - The UK sits as ever at the end of the blocking - & whilst its immediate impacts may be slightly tempered its still expected to impact us ... but how? I would consider the following in terms of probabilities !!! NOT forecasts... * Higher probability of warmer phases in Sept Oct in particular from the south & East * Higher probability that the atlantic jet will be displaced further NW towards Greenland ( although occasional split jets towards Spain & portugal as well ) * Rainfall - Probability should be that its drier however we could up in the unique scenario where the westerly jet runs out of puff over the UK & its very wet ( the weather becomes stationary ) - this would be very unlucky. Also short periods of very high rainfall could occur * Whilst the probability remains high that it will be warmer than usual - the locality of that blocking high means that as we transition through Oct & Nov the chances of early season chill & cold could also be higher- We could see drastic swings in the weather from extreme Mild & warmth to Cold as the jet flow will be buckled... - Also there could well be some overlap into December in these conditions - Highlghted below-- The transition from Autumn & Winter this year will see the usual array of teleconnections to measure up- Currently - ENSO appears to be Neutral out to December, possible low end El Nino, critically here the lower we stay the weaker the impact will be - QBO - decending Westerly at the moment, whilst this isnt great in the long run the effects of the 'westerly' are unlikely to impact until the late part of winter perhaps reducing the prospects of a SSW ( other factors like MJO activity may support either way ) - Sunspot activity continues to be at a low point in the cycle which is a huge positive- - The troposheric disconnect that may well run through sept > Oct could Extend to Nov > Dec for 2 reasons * The feedback from the ice anomalies is so significant that if on average the signal in the last decade is muted out mid Oct - then how long will the new record low take to mute out ?? Another 4 weeks ?? Plus the wildcard this winter may be that theres support for the feedback from greenland in the form of more warmth due to record low ice here as well Plus the stratosphere is being modelled to be weak- The mean of the all the CFS runs should be taken with a pinch of salt - however its modelling significant weakness as we head through Oct & Nov - Further delaying the onset of the westerlies... So there we go as I see it - Autumn - Blocking to the East supports weaker westerlyness - although the UK could sit on the periphery where the jet holds stationary - ( worst case scenario ) Best case scenario >> Jet up to iceland & warmth Winter - Everything is in place to positively support a blocked winter - however the last peice being the strat will only become clearer in another 8-10 weeks ... Best S

On forest gin should be well p I see d soon

In spite of the dry summer garden has done very well,huge crop of plums,huge apples and even a few pears Veg are big too carrots parsnips beetroot cabbage sprouts runner beans and parsnips are all huge. Only the peas seemed to senace early in a drier patch. Perhaps its got something to do with all the farm dung I dig in. Cool dry day currently 8c

Shhhh! They're safely locked-up. I hope

Not a bad day ,480c with sun ,toasty ...

This offshoot from Leslie running along the front is not without interest As it deepens rapidly with some quite cold air behind

2-6 inches in Montana, Wyoming, South Dakota and even a touch in Nebraska. 3rd snow into the US even though we've not got to October yet. https://climatereanalyzer.org/wx/DailySummary/#seaice-snowc-toposu Meteo's global snow forecasts have lots to come in the next two weeks including snow to low levels across northern Scotland at the end of next week. Also watch for California, Great Lakes, North Korea, Balkans and South of France/Pyrenees. http://www.meteociel.fr/modeles/gfse_cartes.php?mode=16&ech=204&carte=1

Lovely spot. Much clearer up North this morning on Sat24.com. Hopefully heading our way.

First day of proper frost and the husband is oot happily swearing away scraping the car. Ah the sweet sounds of winter..

Quickly changing airmass in the fluid pattern

A day of contrasts. Started overcast, windy and mild - 14.5C at 9am. Then a cold front came through around 10:30, marked by torrential rain for a few minutes and very gusty winds. The temperature drop accompanying the front was impressive - down from 14.5C to just 8.9C in no more than 30mins. Light rain on and off after that until 2pm when blue skies reappeared and the rest of the afternoon a mix of sunshine and cloud with a few light showers in the evening - temperatures recovering in the afternoon to a max of 11C, a good 10C lower than yesterday Cold night ahead, already down to 5C. First really large skein of geese passed overhead this evening, plus not seen the house martins the last couple of days. No mistaking now the change of season.

Muchas gracias squire!

Medicane Zorbas Track:

There is very little correlation with the CET however winters that saw at least two months with weak and positive ONI values are (i have included the year as the January one).. Weak.. 1952 1954 1959 1970 1977 1978 1980 1988 2003 2005 2007 2015 Moderate.. 1964 1966 1969 1987 1995 Strong.. 1958 1973 1983 1992 1998 2010 2016 In terms of the CET.. A weak Nino in December favours 5.6C+. A moderate Nino in December favours a high amplitude CET (either 3.6C< or 5.6C> - equal likelyhood). A strong Nino in December favours a close to average CET (3.7-5.5C). A weak Nino in January favours 3.4C< CET (i.e. colder than average). A moderate Nino in January favours 3.4C< CET (i.e. colder than average). A strong Nino in January favours a close to average CET (3.5-5.3C). A weak Nino in February favours a close to average CET (3.7-5.5C). A moderate Nino in February favours a CET of 3.5C or above (equal chance of close to average or above average). A strong Nino in February favours a close to average CET (3.5-5.3C). ....... Worth saying that the winter of 2010 is a strong anomaly for any Nino winter.

A cracking sunset

Very wet this morning after a mild drizzly night.Has cleared to a fine blue sky and light shower cloud .Much cooler though now . A photo of self seeded sunflower in strawberry patch.It only germianated in early August and is now flowering.

The vortex strength at this time of the year is not particular indicative as to how it might progress. The chart below shows the correlation between the 10mb zonal wind and its strength at intervals between 7-42 days later. At this time of year (end of September / start of October) the predictability is at its lowest, only correlating a week in advance. At the end of October / start of November the zonal wind is fairly predictable a month and a half ahead as the vortex is properly formed at this point and is generally too early for major warmings in this period. After this, long term correlations fall as warmings affect the dataset, but short term the vortex increases in predictability for one and two weeks in advance and is fairly stable up to three weeks - the kind of timescales that warmings may take to materialise.

Sea ice has jumped in the last couple of weeks across northern Canada and is above average for the date for the first time in a decade. The last time it was this icy for the time of year was 2004 and, before, that 1996. This year: https://ice-glaces.ec.gc.ca/prods/CVCSWCTWA/20180924180000_CVCSWCTWA_0010248250.pdf https://ice-glaces.ec.gc.ca/prods/CVCSWCTEA/20180924180000_CVCSWCTEA_0010248245.pdf And the last 4 decades at this at this date: https://ice-glaces.ec.gc.ca/prods/CVCHDCTWA/20180924180000_CVCHDCTWA_0010248247.pdf https://ice-glaces.ec.gc.ca/prods/CVCHDCTEA/20180924180000_CVCHDCTEA_0010248243.pdf It's tempting to say its just ice pack movements to that side from Russia but there has also been a trend of increasing ice in Hudson Bay, Eastern Canada and the Great Lakes in recent years as well, so it might not just be Canadian Arctic. Also, the Baltic Sea has seen ice moving back closer to average as well. Blips - or maybe late 70s hot dry summers and cold snowy winters making a come-back (depending where you live)?

A very recent scientific paper (published Sept 24th 2018) and titled "Changing state of Arctic sea ice across all seasons" provides some worrying quantification of the impact of warming in the Arctic. Here are some of the main conclusions: Ice cover has not only retreated in its areal extent, it has also become much younger and thinner in recent years. In April 2018, only about 2% of the winter sea-ice cover consisted of sea ice older than 5 years, compared to almost 30% of the April sea-ice cover in 1984. Accelerated sea ice loss during all months of the year is additionally driven by a lengthening of the melt season. As assessed for the Arctic as a whole through April 2018, melt onset is occurring 3 days earlier per decade, and freeze-up is happening 7 days later per decade. Over the 40 year long satellite record, this amounts to a 12 day earlier melt onset and a 28 day later freeze-up. The primary cause of the ongoing changes in all months are anthropogenic CO2 emissions, with a clear linear relationship between sea ice loss and cumulative anthropogenic CO2 emissions in all months. Extrapolating the linear relationships into the future, we find that the Arctic Ocean completely loses its ice cover throughout August and September for an additional roughly 800 ± 300 Gt of anthropogenic CO2 emissions. For an additional 1400 ± 300 Gt of anthropogenic CO2 emissions, we estimate the Arctic to become sea-ice free from July throughout October. I've been active over the summer months helping build a Research Portal over on the American weather forum 33andrain. You can find the abstract and link to the above paper here: https://www.33andrain.com/topic/1422-changing-state-of-arctic-sea-ice-across-all-seasons/ And there are many other papers in the Research Portal about Arctic Amplification (Warming) and Sea Ice Loss, so please feel free to take a look. The Index to the research facility is here: https://www.33andrain.com/topic/996-index-to-papers-and-articles/

Strong sense of deja vu here as the POL was brought up in the discussion on the OPI back in 2014. At almost the same time the concept of the Taymyr Circulation Anomaly came to the fore in the paper October circulation precursors of the wintertime Arctic Oscillation (Kryjov 2014). This highlighted the correlation between Taymyr October geopotential anomalies and the following winter AO, but it seems the paper is still paywalled. At the time an arbitrary point was used to investigate this correlation (74.5°N 104°E) using 500hPa geopotential. However, the author co-wrote a follow-up paper Predictability of the wintertime Arctic Oscillation based on autumn circulation (Kryjov & Min 2016) which gives an insight to the earlier work and its application to forecasting (they use 700hPa geop. anom averaged and area weighted over 80-70°N 100-120°E). This paper is available - https://www.researchgate.net/profile/Vladimir_Kryjov/publication/292075140_Predictability_of_the_wintertime_Arctic_Oscillation_based_on_autumn_circulation/links/56c3f03708ae8a6fab5a3396/Predictability-of-the-wintertime-Arctic-Oscillation-based-on-autumn-circulation.pdf As illustrated in 2014, the homebrew Taymyr index proved superior to the POL in correlations with the AO, below are the correlations from 1950 up to last winter - Winter AO Dec AO Jan AO Feb AO Taymyr index 0.390 0.265 0.342 0.258 POL index 0.182 0.090 0.145 0.167 In particular it supports the link between October circulation and winter AO suggested by Kryjov. This doesn't tell the whole story however as shown in this chart of running 20-year correlations between the indices and winter AO. Also included are a Mongolian z500 anomaly (50°N 120°E) which has been used to create an estimated POL - The first few years are poor for all, this may be due to issues with data quality in the early reanalysis - the authors above use from 1958 onwards. After this though, the Taymyr index is better than the POL except for the 3 year period 2005-2007 (interestingly the artificial POL also beat the Taymyr), but more than this it proves to be relatively stable providing consistently good correlations over time. The same can't be said of the POL however which is poor in the early years even anticorrelated to winter AO and this is more strongly the case for the Mongolian anomaly - it would suggest that the value of the POL is given by the node in the area of the Taymyr circulation and it is dragged down by its dipole in Mongolia. In the second half of the period the Mongolian anomaly correlation improves which leads to better performance from the POL and there is also quite a marked sudden improvement for all including the Taymyr index. Couple of possibilities spring to mind - the timescales of Mongolian and POL correlations with winter AO are similar to the AMO. The 30 year correlation between the Mongolian anomaly and October AMO exceeds -0.7 when AMO leads by 29 years - but is >0.8 when AMO lags by 9 years (with over 0.95 for 10 year averaged AMO) - because of the timescales involved more data would be required to investigate this link further. The apparent sudden improvement in all indices may coincide with improved reanalysis with satellite data maybe. Finally with regards to changes since 2007, it is worth noting that all the correlations have fallen since the 2007-12 period.

Part 1 http://www.youtube.com/watch?v=PFgIhdzV4tw...ted&search= Part 2 http://www.youtube.com/watch?v=KwQVUTlrLfE...ted&search= Part 3 - You Can See The Tornado Forum In The Back Ground http://www.youtube.com/watch?v=IROmLnLmr1Y...ted&search= Last Part When They Lost Power http://www.youtube.com/watch?v=ZccjWPB42NI...ted&search= Sorry If Wrong Place

Update for the week to September 23rd The current 5 day trailing average is on 4,814,000km2 while the 1 day extent is at 4,839,000km2. (All the following data is based on a trailing 5 day average) The daily anomaly (compared to 81-10) is at -1,589,000km2, a decrease from -1,625,000km2 last week. The anomaly compared to the 07, 11 and 12 average is at +683,000km2, an increase from +638,000km2 last week. We're currently 8th lowest on record, down from 7th lowest last week. The average daily change over the last 7 days was +22.2k/day, compared to the long term average of +17.6k/day, and the 07, 11 and 12 average of +16.3k/day.The average long term change over the next week is +43.7k/day, with the 07, 11, and 12 average being +29.9k/day. The extent change so far this September is the 20th least negative on record. To achieve the largest growth, an increase of at least 123.0k/day is required (more than 167.2k/day with single day values), while the largest loss requires a drop of at least 30.6k/day (drop of at least -47.7k/day with single day values) and an average change requires an increase of 40.8k/day (52.2k/day with single day values). The 5 day average value of 4,635,000km2 from the 13th is likely to be the minimum for the year. This is the 8th lowest on record.