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... and I still remember the bone chilling November of 1985 when this very similar chart: became this: which then turned into this:

MJO did crossover back into phase 8 briefly and has now moved back into phase 1, very fascinating behaviour with either phase 8 or 1 since 15th September so now a whole month and looking like at least a bit longer on top of that http://www.bom.gov.au/climate/mjo/graphics/rmm.74toRealtime.txt so something similar to the latest GFS run may not be too far off the mark with the general idea of higher pressure toward Greenland (possibly still some drier weather over UK during next week) then possibly the higher pressure moving from Greenland toward Scandi like the GFS hints at https://docs.wixstatic.com/ugd/31d9e0_3c062d439cb841d2eea3ea174256642b.pdf Certainly shaping up to be an interesting few weeks.

Heard the words Indian summer and broke out into a cold sweat, if you pardon the pun. For me we are potentially looking at the increasing risk of a colder spell later this month, with more and more ensembles beginning to flag it up! Early taste of winter, or late burst of summer!! For me the Indian summer can stay in India....

Some respite after the weekend from the relentless rain, but thereafter, it is not easy to see the path. Consider the T240 charts from GFS, GEM and ECM 12z: Tropospheric vortex looks in considerable turmoil, but up above it's a different story as the icy whirlwind in the stratosphere really takes hold, getting cold up there, GFS T240: And the forecast is for a considerable strengthening of the vortex now, zonal wind: This disconnect cannot go on for ever, so does the trop fall in line with the strat and we get a horrid wet and windy Atlantic dominated November, or are we headed towards an early warming for the strat, putting the brakes on or more...well we will need to see some pressure put on the strat vortex, GFS T384...??? We will see...

Here's my contribution to the discussion: The following is a preliminary long-range forecast for winter 2019-20, If it seems necessary, I will amend or update this forecast in mid-November. This appears likely to be a season where high energy weather events will be grappling with a fairly robust supply of colder air at high latitudes. Britain and Ireland can expect a very unsettled winter with frequent low pressure systems steered by a strong jet stream running a little south of its average position. This favours a split north-south outcome where the south is often on the milder side of the storm track getting strong southwest winds and rain, while the north is more open to snow, ice and easterly winds. The north-south divide may be enhanced by the likely appearance of strong blocking highs over eastern Scandinavia and western Russia. I don't think these are going to dominate the circulation but they will come into conflict with the zonal regime at times, forcing it to dive southeast around 5-10W and into France and the western Mediterranean. This may be another winter of heavy Alpine snowfalls and frequent severe cold spells in Germany and possibly Belgium and Netherlands into northeast France. Battleground conditions seem likely at times across southeast England into Wales and central to northern Ireland. Frequent snow events may occur in northern and even central England, and southern Scotland, also Northern Ireland and some adjacent parts of the Republic of Ireland. Some heavy precipitation is likely in this scenario, heavy rain in most cases in southern England, especially the southwest, and the southern third of Ireland (Munster and south Leinster). A set-up like this may not remain steady-state, but could fluctuate north-south bringing the milder conditions further north at times, while setting the battleground further south at other times. However, the tendency will be for temperatures to average closer to normal or above in the southwest, and below normal in Scotland. This pattern could evolve into a colder February or even March if the strong jet stream loses energy, then the blocking may be able to assert more control. North America can expect a rather harsh winter in general, with severe cold waves at times, colliding with an active storm track from Texas northeast towards Virginia and southeastern New England. There could therefore be heavier than average snowfalls in the Ohio Valley, Midwest, and inland Mid-Atlantic to northeastern states. A pattern like this would not rule out one or two coastal blizzards in the mix. The west will be dominated by persistent cold high pressure trapped in valleys, and coastal areas will have a fairly average winter with a lot of rain, low cloud and moderate southeast winds. Snow on western mountains will be generally a bit above average but might be twice normal in the southern Rockies and northern Arizona around Flagstaff. Drought will break during the winter for California. This may also be one of those winters where extreme cold moves south from Siberia into China, Korea and Japan.

Hello sir!!! BOOM!

Looking a bit further ahead, here's the last 5 NH Z500 anomalies for December from the CFS (averaged over the month): Setting aside UK potential, how many scream a raging +AO? None. Hmmm...

Long fetch northerly at T240 on the FIM8: Just for fun!

Well it's that time of year when it's time to dust off the keyboard. I hope you have all had great summertimes. What a thing of beauty the GFS12z is today. It's been in the offing for 48 hours and, truth be told, we'd all much rather we saw it in December than October. Still, it's comforting to know that blocking hasn't disappeared from the earth or that the fabled Greenland High is just a thing of legend.

Big cold pool building on the continent at 240 on the ECM

There are indeed some really nice ensembles showing around day 10 onwards on the GEFS .

What is it with the control run of late spawning charts worth dwelling over lets take a look at it it all happens around day ten(yes i know it's day ten sigh) deep trough in N Canada forces WAA ahead of it up the west side of Greenland(black arrow),also notice the arctic high(white circle) creating some reverse -AO(arctic oscillation)(orange arrow) forcing the trough west of Greenland south lets have a look at the animated sequence of both the 500mb height's and 850. ' will it set a trend?

Just wondering whether to tell my family about the risk of snow later next week on the GEFS 6z?❄...there's certainly some Arctic potential..just waiting for Exeter to jump on board

Wednesday morning looks like a wet start for many eastern and central areas of England, with a band of rain, perhaps heavy, will move NE across the British Isles. Places like northern England and Scotland should also be under this heavy rain too. SW England, Wales and Northern Ireland will wake up with a dry start, but not TOO dry, as the band of heavy rain should of progressed over these places in the early hours of Wednesday. Northern Ireland has the best chance of waking up to some glorious sunshine, which a small chance of catching the odd shower or two. As the day progresses, and we head into the afternoon, it should start to brighten up across the majority of England and Wales as the band of rain spreads NE, except Norfolk, where they might catch some drizzle. Where places across England get sunshine, it won't be crystal clear, there might just be some fair weather clouds lurking in the sky. Wales should remain dry for the rest of the afternoon, with the small chance of catching an isolated shower. The band of rain also clears NE across northern England and Scotland, and into the afternoon the majority of those areas should also remain dry for the rest of the afternoon, except NE Scotland, where they could catch some drizzle. Northern Ireland could remain dry for the whole day, with, once again, the exception of the small shower. If you do catch a shower, it shouldn't be too heavy. Into the evening, most places of the United Kingdom should remain dry, with the chance of catching the odd shower across SW England, Wales, northern England, Scotland, and Northern Ireland. To the far SE of England, there is a small chance that they could catch some rain into the evening. Other than that, some places have the chance of catching some sunshine to end the day. The peak temperatures in the afternoon in the south should range from 10-16c, and in the north should range from 7-15c.

Not sure if anyone has mentioned the Ecm 0z operational T+240 hours..so I will..it's preety good in an indian summer kind of way!

Ding dong! Some early-season FI eye-candy to enjoy...? Not a great deal of support from the GEFS 00Z ensembles, though: Winter, she's a'comin'!!!!?️

Evening everyone,i see the gfs is still at it with forecasting a northerly outbreak later next week so it is consistent,just need the ecm to come on board,if you look at the mean at day ten from both the gfs and ecm they both look broadly similar with the height's pushing up into Greenland so i think the ecm op may come on board tomorrow the latest from cpc days 8-14 show this with height's pushing up into Greenland with trough down into Scandinavia now for the flip of the coin,the NAO/AO was forecast to go +ve positive yesterday,now look at them,if this continues then the Atlantic door may be come ad-jarred or even shut i know i am ramping a little bit but who wouldn't now for the 18z,buckle up.

Plausible?

Variation of the theme height rises bringing in chillier temps and more settled conditions. Edit and agin rises towards greenland.

outlook - This weeks weather will be dominated by the Atlantic low as it drifts east and fills The North Atlantic 500mb and surface analysis for midnight and current sat image With yesterdays wave and front out of the way it will be a pretty overcast start to the day in many central and eastern regions but this should improve with everywhere having not a bad day with some sunshine. A few showers in the south east this morning and the south west later but other wise pretty dry which is a tad unusual of late. But the fronts associated with the aforementioned low are approaching from the west and rain will effect N' Ireland and the south west by evening and this will track across the country overnight to be aligned western Scotland > south east England by dawn The fronts will continue to track east through Wednesday and much of the rain should clear by lunchtime but a few hours later in the north and south east. It should quite sunny behind all of this, albeit a few showers in western regions By Thursday the low is west of Ireland with the associated occlusion over same thus the UK in a brisk south westerly wind with sunny interval and showers which will be mainly concentrated in the west. Over Friday and Saturday the low continues to fill over th UK as it nestles between the amplifying subtropical high zones but a lot of pressure is being exerted in the Atlantic as energy sweeps east across the US. Essentially then a couple of days of sunshine and showers which could well be heavy with thunder in the mix. Temps around average

Another trigger over Greenland about to be pulled for second more potent go. -6c already there with -8c just waiting in the wings. Heavy snow for some places.

The next 4 weeks in terms of polar heights feel like they are going to be very important in the grand scheme of things in terms of seeing how the predisposed troposphere which thus far has been primed towards a -NAO comes up again a record cold stratosphere trying to down-well to the surface- Its at this point you would expect based on history for the models to trend towards significant positivity on the AO & NAO & repeatedly the modelling does reflect that in the day 11-16 arena however as we move into the day 8-11 timeline the trends are opposite for the polar field & look more blocky. If we take todays ECM day 7 & below put the day 10 chart from 3 days ago you can see how the +AO has been overestimated with the vortex now modelled to be pushed out of the pole again- We can also see a wedge of higher heights over the pole in the mix now- So what was modelled to become a positive AO is now likely to be neutral at best. As we head out to day 10 on tonights ECM the heights point to a slightly negative AO This isn't really consistent with the coupling of the Trop > Strat & should these charts come to verify with a -NAO & -AO then this should give us more confidence as we head to winter that the seasonal models could be wrong. Also just a footnote on them- the enhanced azores high could be modelled correctly in terms of additional depth over winter however its location could be more vertical in lattitude with the icelandic low be positioned more Eastward - This would bring a whole different weather pattern to the UK away from mild & wet.... S PS its also worth noting that on October 13th the sea ice extent dropped back below the record low 'recovering' 2012 by 30k - The last 30 or so days have seen the deficit of about 600KM2 slowly reduce with a combination of low increases interspersed with occasional loss days so the growth curve has been very weak leading to the crossover day yesterday. Its unlikely ( based on current rate of growth & the +SSTA ) to catch back up in the very near future.....

Here are the GEFS 12Z ensembles: something quite cold (judging from the Op and Control runs) looks quite likely; however, when T850 and 2m temps are at their lowest, there's little or no precipitation predicted. Sod's Law or what! Even for here on the Norfolk-Suffolk border!

Definitely a rather interesting output from the gfs to say the least would feel wintry indeed at times but unreliable time frame so health warning with that. High pressure struggles to build in according to the gfs next week too.. We'll see.

Up she goes early doors.

Careful, don't want to go with any "definites" this far out. Twill go titticus verticus if we're not careful!

A Nina-like atmospheric state with a poorly organised tropospheric polar vortex (despite the stratospheric one being much more so) can facilitate some nice 'tall' mid-Atlantic ridges in Oct-Nov, maybe early Dec. Not sure how much longer the trop. vortex will really be able to stay so disorganised, though. Anomalously large Arctic heat + moisture fluxes are a wildcard, as usual in these times of huge sea ice deficits. Regardless, I expect we'll have a few 'toppler' scenarios to ponder over in the coming weeks. Going to be tough for low levels to get much wintry weather out of such things, though. It's not going to help sanity levels that the FV3 core of GFS still seems to have a bit of a cold bias with troposphere temps.

I’ll be doing my LRF early this year as I believe Nov has a chance of being classed as a winter month. But the issue I’m dwelling on is that I believe we’ll be relying on pM air turning into arctic maritime shots with HP to our W/SW playing it’s part (and with pronounced energy peaks could be very tasty)and I’m not wavering from that POV. Scotland, NI and Northern England to definitely benefit but what about the rest....it needs the type of GFS set ups in deep FI we are seeing to come to fruition. BFTP

It certainly would, above average heights NW with a\ trough over Italy w3 then above average heights over Scandi w4.

The control is at it again all be it deep in FL.

So to the pub run, first at T156, ridge of high pressure will be a relief to those who have had incessant rain recently. From then on, well this looks like a flying pig: Well it does to me anyway, coming at you view... you can clearly see its snout, that colder rush becoming more likely?

In my post yesterday I said one possible scenario for later in the month was for a NW then northerly flow - indeed GFS showing this today with strong Greenland high. ECM less keen, but still shows blocking by the end of this week and into next week to our north and north west.

This looks -- as it's only October -- very good; probably nae much snaw, away from Scotland, but plenty of coastal convection?

Looks like we could be in for one of those late autumnal week's where one day you're wearing a cardi and the next a thick winter coat and scarf!!! Love seeing the seasonal changes in full force!x

Sorry but if you want to go all technical and that we had a white Christmas 2009 NI from a weather front pushing in against the already cold condition's that had set in the weeks before. Temps on the big day were really cold in mid-ulster -5 freezing fog for most of the day before the system came in i can remember it fondly Northern Ireland has first white Christmas in five years WWW.BELFASTTELEGRAPH.CO.UK The prayers of thousands of men, women and children were answered yesterday as Northern Ireland had its first white Christmas in five years. Britain enjoys first white Christmas for five years WWW.TELEGRAPH.CO.UK Britain has had its first official white Christmas for five years after snow fell in at least two parts of the country.

I am surprised as I didn't realize you were into south westerly zephyrs

Yesterday's rainfall totals nowhere near as much as forecasts had suggested. Definitely a bust for most of the Region. Here's the Netweather Extra 24 hour rainfall totals up to midnight, calculated using 1km radar data:

A cursory glance the latest EC46 update for the first couple of weeks for November leaves one a tad optimistic. Generally pressure is quite high over the UK in the fairly weak upper flow with low pressure developing over Greenland during the second week so still tending towards a N/S split. The precipitation spread indicates this whilst temps are around average, It would be grand if this presaged the winter trend

And the 06Z finishes on one of those pesky 'if only it were either January or July' synoptic patterns: And with the Operational and Control both in the same ballpark, T850s of -5 to -7C look perfectly possible ?️...? I'm glad I got that in before the 12Zs come out and ruin it!

Never knew this thread was about still. well last white xmas for me was 2017. it was 13c at dinner 1pm and we had the windows open, by 10pm it was snowing so technically a white xmas, but for me it really has to be a good cover with either ice cold and clear or ice cold and more snow falling.

@Norrance and @Kirkcaldy Weather posting filthy weather porn in the snow and ice thread... some stunning stuff just dont tell mrs Big Snow ive been looking at it..

Yea followed by an Arctic outbreak shortly after.

Indeed, maybe an indian..summer according to the Ecm 0z!

Mind you, I know I'd like to have plenty of lying snow in brilliant freezing sunshine on the big day rather than nothing sticking and a few flakes falling. Just my personal opinion, but an 'official' white Christmas isn't always great.

The GEFS 0z mean is certainly very interesting further ahead, portends increasing chances of Polar / Arctic maritime shots!❄

Right on cue, fairly potent (for the time of year) this run came out with a few ens members to back it up.

My eyes light up when I see Arctic potential whatever the timeframe..and even more when I see snow appearing on the ensembles..in october!!..here's hoping for a looooong winter with plenty more charts like these..white Halloween anyone?!!!!❄❄❄❄❄❄

The Santa shaker will be back at the beginning of November Christmas Weather Forecast - White Xmas 2018 WWW.NETWEATHER.TV

Solar activity and the 6 severe winters of the 20th century (sub 2C for CET) 1916-17 (just before maximum) 1928-29 (just after maximum) 1939-40 1946-47 (just before maximum) 1962-63 1978-79 (approaching maximum) 4 of them occurred within a year either side of solar maximum. None of the other 2 occurred within a year of solar minimum.